Class Definition for Class 84

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CLASS 84,	MUSIC
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SECTION I - CLASS DEFINITION

This class includes the instruments used in producing music and includes (1) electrical music instruments, (2) automatic instruments, and (3) those hand played. The automatic instruments and the hand played instruments have a parallel classification so far as seems practical, and in both the patents are divided in the usual way into four groups, stringed, wind, rigid vibrators, and membranes. Then follow details or features common to groups (1), (2), and (3). This class also includes some accessory devices generally recognized as belonging to the art or industry.

SECTION II - LINES WITH OTHER CLASSES AND WITHIN THIS CLASS

Instruments furnishing a sound of only one pitch, even if it might be used for musical purposes, are generally to be found in Class 116, Signals and Indicators; Class 446, Amusement Devices: Toys, subclasses 207-209 and 397-422; Class 472, Amusement Devices, subclass 64; or Class 623, Prosthesis (i.e., Artificial Body Members), Parts Thereof or Aids and Accessories Therefor, subclass 9 for larynxes.

Phonographs, unless in combination with a recognized musical instrument, are to be searched for in Class 369, Dynamic Information Storage or Retrieval.

Printed music and systems of notation are to be found in Class 84 (this class), Music, subclass 483.2.

Bellows and wind flow regulators, unless specifically adapted to musical instruments are to be found in Class 60, Power Plants; subclasses 407-412; Class 91, Motors: Expansible Chamber Type; Class 92, Expansible Chamber Devices; and Class 417, Pumps.

Many features of construction or manufacture should be sought for in woodworking or metal-working and many details not limited to this art in appropriate classes, such as pedals, supports, clamps, cases, springs, etc.

For instrument supports of general application not claimed in combination with musical instruments or structurally limited to use with specific musical instruments, see Class 248, Supports, appropriate subclasses.

SECTION III - REFERENCES TO OTHER CLASSES

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclass 118 for amplifying and reproducing the sounds of musical instruments.
984,	Musical Instruments, an alternative search of the type of subject matter generally found in Class 84 may also be found in Class 984 which is based on a modification of the European Patent Office.

SUBCLASSES

1	INSTRUMENTS:
	This subclass is indented under the class definition. Patents not classified in any of the subclasses below.

[List of Patents for class 84 subclass 2]

Combined:

The instrument includes two sets of sounding-bodies which belong to different groups, as specified above.

(1) Note. Drums, chimes, etc., used as attachments to pianos belong here or in subclass 3 or subclass 6.

3	Electric:
	The instruments have electric circuits.

[List of Patents for class 84 subclass 4]

With phonograph:

This subclass is indented under subclass 3. A piano or other accompaniment is provided for a phonograph cylinder or disk.

SEE OR SEARCH CLASS:

352,	Optics: Motion Pictures, subclasses 12 through 24for synchronizing a sound-producer with a cinematograph.

5	Electrical connections:
	This subclass is indented under subclass 4. The synchronizing devices include electric circuits.

6	Pneumatic:
	This subclass is indented under subclass 3. The sounding-bodies of one or both sets are operated by player-pneumatics.

7	Stringed:
	String-playing devices not belonging in a specific subclass.

8	With picking devices:
	This subclass is indented under subclass 7. Self-playing banjos, mandolins, zithers, etc., often with fingering devices and pneumatic mechanism.

9	Electric:
	This subclass is indented under subclass 8. The instruments have electric circuits.

10	With bowing devices:
	This subclass is indented under subclass 7. Self-playing violins, usually with fingering or stopping devices, sometimes with pneumatic mechanism.

11	Electric:
	This subclass is indented under subclass 10. The instruments have electric circuits.

12	With striking devices:
	This subclass is indented under subclass 7. Stringed instruments of various types with strikers, sometimes operated by pneumatics.

[List of Patents for class 84 subclass 13]

Pianos:

This subclass is indented under subclass 7. Patents for the complete instrument or for features not specific to a subclass below.

SEE OR SEARCH THIS CLASS, SUBCLASS:

105	through 114, for players readily removable from the piano and applicable also to a reed-organ keyboard.
115	through 166, for an invention limited to features of the selecting mechanism.

14	Without keys:
	This subclass is indented under subclass 13. Instruments of the piano type for automatic playing exclusively.

15	Half width:
	This subclass is indented under subclass 14. Automatic pianos having the strings in two narrow sets.

16	Constant power:
	This subclass is indented under subclass 13. The blow is struck by power derived from a rotating shaft or other constantly-operating source.

17	Electric control:
	This subclass is indented under subclass 16. The connections between the source of power and the strikers are controlled electrically.

[List of Patents for class 84 subclass 18]

Key actuators:

This subclass is indented under subclass 17. The power acts directly on the keys.

(1) Note. Most of the patents in this and in the preceding subclass are of the roller-and-shoe type.

19	Electric power:
	This subclass is indented under subclass 13. The power is derived from a source of electricity.

20	Key actuators:
	This subclass is indented under subclass 19. The power acts on the keys.

21	With expression:
	This subclass is indented under subclass 20. These patents include means for varying the force of the blow, usually electric resistances.

22	By voltage change:
	This subclass is indented under subclass 21. Expression is secured by varying the voltage.

23	With expression:
	This subclass is indented under subclass 19. Devices similar to those of subclass 19, but the piano-key is not involved.

[List of Patents for class 84 subclass 24]

Pneumatic type:

This subclass is indented under subclass 13. This is the common type of player-piano wherein the blows are caused by small bellows called "striker-pneumatics", one to each hammer.

(1) Note. The patents classified herein generally disclose a complete mechanism and often claim details of selecting mechanism as well as the playing mechanism.

[List of Patents for class 84 subclass 25]

Key actuators:

This subclass is indented under subclass 24. Like the preceding subclass except that the striker-pneumatic acts on the key.

SEE OR SEARCH THIS CLASS, SUBCLASS:

105	through 114, for this feature.

26	Grands:
	This subclass is indented under subclass 24. Patents showing a pneumatic action built into a grand piano.

27	Connections to piano action:
	This subclass is indented under subclass 26. Patents claiming novelty in the connections from the pneumatics to the grand-piano action.

28	Action above keyboard:
	This subclass is indented under subclass 24. Limited to patents in which the claims in terms or in substance require the striker-pneumatics to be above the keyboard.

29	Action below keyboard:
	This subclass is indented under subclass 24. Similarly limited to cases having the pneumatics below the keyboard.

[List of Patents for class 84 subclass 30]

Location of parts:

This subclass is indented under subclass 24. Patents in which the parts are fitted into the piano in a novel way or are located in unusual positions.

SEE OR SEARCH THIS CLASS, SUBCLASS:

116,	for patents wherein only the tracker-box location is novel.

[List of Patents for class 84 subclass 31]

With double tracker:

This subclass is indented under subclass 24. The tracker has two sets of rows of note perforations, both normally in use to obtain expression.

SEE OR SEARCH THIS CLASS, SUBCLASS:

146,	148, and 152, for sheets and trackers.

32	Double length:
	This subclass is indented under subclass 31. The two rows are in the same line, so that the tracker is longer than usual.

[List of Patents for class 84 subclass 33]

Expression mechanism:

This subclass is indented under subclass 24. Miscellaneous devices for giving expression to the music.

(1) Note. In the art, the term "expression" usually refers only to controlling the force of the blow.

SEE OR SEARCH THIS CLASS, SUBCLASS:

128,	through 131, for tempo control.

[List of Patents for class 84 subclass 34]

Parts of piano moved:

This subclass is indented under subclass 33. The pedals or other parts of the piano are moved for expression.

SEE OR SEARCH THIS CLASS, SUBCLASS:

216	through 224, for expression devices.

[List of Patents for class 84 subclass 35]

Rest rail shifted:

This subclass is indented under subclass 34. The hammer rest-rail is shifted, usually in sections and without depressing the pedal.

SEE OR SEARCH THIS CLASS, SUBCLASS:

219	through 223, for pianissimo devices.

36	Normally in short stroke position:
	This subclass is indented under subclass 35. Normally the hammers are in position for pianissimo effect.

37	Position controlled from reservoir:
	This subclass is indented under subclass 35. The rest-rail is automatically shifted as the wind-pressure in the reservoir varies.

38	Graduated shift:
	This subclass is indented under subclass 35. The ends of the rest-rail may move through unequal distances, so the musical effect is graduated from bass to treble.

39	Wind pressure varied:
	This subclass is indented under subclass 33. The pressure of wind supplied to some or all of the striker-pneumatics is varied to obtain accent.

40	By pumping:
	This subclass is indented under subclass 39. The variation is due to a change in the pumping.

41	By throttling:
	This subclass is indented under subclass 39. The variation is due to a change in the cross-section of the wind-passage.

42	By regulating chamber:
	This subclass is indented under subclass 39. The variation is due to the action of a variable chamber additional to the reservoir.

43	By use of two pressures:
	This subclass is indented under subclass 39. The variation is due to the alternate use of two wind-chambers holding air, respectively, at high and low tension.

44	Two cooperating pneumatics to each note:
	This subclass is indented under subclass 33. There are two striker-pneumatics for each note, one or both of which may be used.

45	Two opposing pneumatics to each note:
	This subclass is indented under subclass 33. The movement of the striker-pneumatic may be retarded by another pneumatic.

46	Transmission varied:
	This subclass is indented under subclass 33. The fulcrum of a lever is shiftable or the connections between the pneumatic and the hammer are otherwise varied.

[List of Patents for class 84 subclass 47]

Systematic variations:

This subclass is indented under subclass 33. The force of the blow is systematically or periodically varied independently of the hand-controllers or note-sheet.

SEE OR SEARCH THIS CLASS, SUBCLASS:

157,	for devices to avoid mechanically accurate playing.

[List of Patents for class 84 subclass 48]

Pneumatic details:

This subclass is indented under subclass 33. Pneumatic details limited to parts of the expression mechanism.

SEE OR SEARCH THIS CLASS, SUBCLASS:

50,	for similar constructions which do not have this limitation.

[List of Patents for class 84 subclass 49]

Hand controllers:

This subclass is indented under subclass 33. Levers or buttons for controlling expression. The patents generally show also tempo-controllers.

SEE OR SEARCH THIS CLASS, SUBCLASS:

164,	for expression and tempo marks.
169,	for indicators.

[List of Patents for class 84 subclass 50]

Pneumatic construction:

This subclass is indented under subclass 24. Improvements in the controlling parts between the reservoir and the striker-pneumatics.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48,	for pneumatic details limited to expression mechanism.
79,	for various elements that do not include controlling-pneumatics.

51	Both primaries and secondaries:
	This subclass is indented under subclass 50. The pneumatic train includes both primary and secondary valves, sometimes called the "double-valve system".

52	Lower leaf moved:
	This subclass is indented under subclass 51. The lower leaf of the striker-pneumatic is the movable one.

53	Lower leaf moved:
	This subclass is indented under subclass 50. Like the preceding subclass except that there is no secondary valve.

[List of Patents for class 84 subclass 54]

Striker pneumatics in wind chest:

This subclass is indented under subclass 50. The striker-pneumatics are located in the wind-chest.

(1) Note. Pneumatics in a wind-chest to operate valves are shown in many patents in this art and in the organ art.

55	Units:
	This subclass is indented under subclass 50. The construction involves many duplicate parts that are readily detachable.

56	Metal:
	This subclass is indented under subclass 55. These parts are of metal.

57	Tubes and junctions:
	This subclass is indented under subclass 50. Patents involving the position or location of tubes from the tracker or other part and means for connecting tubes, such as junction plates or bars.

58	Bleeds:
	This subclass is indented under subclass 50. Constructions having minute openings into a passage, especially into a tracker-duct.

59	With valve:
	This subclass is indented under subclass 58. The bleed is closed by a valve during part of the cycle of operations.

60	Valves and seats:
	This subclass is indented under subclass 50. Patents pertaining to automatics having novelty in the valve or its seat.

61	Inside:
	This subclass is indented under subclass 60. Patents for double valves, the operating-surfaces of which face one another.

62	Outside:
	This subclass is indented under subclass 60. Patents for double valves, the operating-surfaces of which face away from one another.

63	Adjustable:
	This subclass is indented under subclass 62. Similar to the preceding except that the distance between the surfaces is adjustable.

64	Screening and cleaning:
	This subclass is indented under subclass 50. Means to prevent dust from entering the action or for removing it.

[List of Patents for class 84 subclass 65]

Power pneumatics:

This subclass is indented under subclass 24. Pneumatics to strike the keys or throw the hammers or exert power otherwise.

SEE OR SEARCH THIS CLASS, SUBCLASS:

50	through 64, for pneumatics that shift the valves.

66	Connections to hammers:
	This subclass is indented under subclass 65. Patents covering various forms of connections between the pneumatic and the hammer.

67	To key:
	This subclass is indented under subclass 66. The connection engages the key.

68	To abstract:
	This subclass is indented under subclass 66. The connection engages the abstract.

69	To wippen:
	This subclass is indented under subclass 66. The connection engages the wippen.

[List of Patents for class 84 subclass 70]

Wind-supply devices:

This subclass is indented under subclass 24. Means not otherwise classified pertaining to the supply of wind.

SEE OR SEARCH THIS CLASS, SUBCLASS:

355,	for wind supply devices.

SEE OR SEARCH CLASS:

417,	Pumps, appropriate subclasses for a pump, per se.

71	In grands:
	This subclass is indented under subclass 70. The construction is specially fitted for grand pianos.

[List of Patents for class 84 subclass 72]

Pedals:

This subclass is indented under subclass 70. Pedals connected to operate bellows.

SEE OR SEARCH THIS CLASS, SUBCLASS:

225	through 233, for piano-pedals.
353,	and 357, for organ-pedals.

73	Folding:
	This subclass is indented under subclass 72. The pedals may be folded into the piano-case.

[List of Patents for class 84 subclass 74]

With keylock:

This subclass is indented under subclass 72. Devices to lock the keys when the pedals are drawn out.

SEE OR SEARCH THIS CLASS, SUBCLASS:

167,	for other key-locks.

75	With doors:
	This subclass is indented under subclass 72. Pedals with doors to hide them.

76	Operating together:
	This subclass is indented under subclass 75. Mechanism to open the doors and throw down the pedals by a single action of the performer.

77	Door-carried pedal:
	This subclass is indented under subclass 76. The pedal is attached to the inside of the door.

78	Upper panel moved:
	This subclass is indented under subclass 76. The panel in front of the tracker-box is shifted simultaneously with the pedal-door.

[List of Patents for class 84 subclass 79]

Distribution:

This subclass is indented under subclass 70. Various elements between the bellows and the controlling-pneumatics, especially reservoirs and wind-chests.

SEE OR SEARCH CLASS:

417,	Pumps, subclasses 279 -311 for pumps having condition responsive control of the fluid handled by the pump.

80	Key slips:
	The key-slip or part of it is movable to uncover or shift various parts preparatory to playing.

81	Upper panel:
	Improvements relating to the panel in front of the tracker-box.

[List of Patents for class 84 subclass 82]

Lower panel:

Improvements relating to the panel in front of the pedals.

SEE OR SEARCH THIS CLASS, SUBCLASS:

75	through 78, for pedals, if claimed.

[List of Patents for class 84 subclass 83]

Wind:

Automatic wind instruments not otherwise classified, as accordions, flutes, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

330	through 401, for features not limited to automatic instruments.

84	Organs:
	This subclass is indented under subclass 83. Miscellaneous organ constructions having either pipes or reeds, or both.

85	Stop actions:
	This subclass is indented under subclass 84. Improvements in the stop-action.

86	Cylinder:
	This subclass is indented under subclass 84. The selection of notes is determined by pins on a cylinder.

87	Disk:
	This subclass is indented under subclass 84. The selection of notes is determined by projections or perforations on a disk.

88	Electropneumatic action:
	This subclass is indented under subclass 84. Electropneumatic organs with automatic control.

89	Pneumatic action:
	This subclass is indented under subclass 84. Pneumatic organs with automatic control only.

90	With keys:
	This subclass is indented under subclass 89. Pneumatic organs with both automatic and key control.

91	Pipe organ:
	This subclass is indented under subclass 89. Pneumatic pipe-organs with automatic control.

92	Organettes:
	This subclass is indented under subclass 83. Small reed-organs with hand-operated bellows and a paper sheet serving as valves for the reeds.

93	Mouth blown:
	This subclass is indented under subclass 83. The instruments are small enough to be blown by the player.

[List of Patents for class 84 subclass 94.1]

94.1

Combs:

Miscellaneous instruments having a comb, the teeth of which are tuned to be the sounders.

SEE OR SEARCH CLASS:

132,	Toilet, subclasses 219 -163 for toilet combs.

94.2	Combined:
	This subclass is indented under subclass 94.1. Miscellaneous instruments combined with other art devices.

[List of Patents for class 84 subclass 95.1]

95.1

Cylinder type:

This subclass is indented under subclass 94.1. Subject matter wherein the teeth of the comb are picked by pins on a rotating cylinder.

(1) Note. Includes Swiss music-boxes.

95.2	Combined:
	This subclass is indented under subclass 95.1. Subject matter combined with other art devices.

[List of Patents for class 84 subclass 96]

Cylinder construction:

This subclass is indented under subclass 95.1. Details of the construction of the cylinder.

SEE OR SEARCH THIS CLASS, SUBCLASS:

86,	for cylinders having pins determining note selection.

SEE OR SEARCH CLASS:

492,	Roll or Roller, subclasses 30 -37 for a roll, per se, not elsewhere provided for, with a working surface having projections, indentations, or slits.

[List of Patents for class 84 subclass 97]

Disk type:

This subclass is indented under subclass 94.1. The teeth of the comb are picked by projections on a rotating disk.

(1) Note. Includes Regina music-boxes.

98	With star wheels:
	This subclass is indented under subclass 97. Star-wheels are used between the disk and comb.

[List of Patents for class 84 subclass 99]

Multiple disks:

This subclass is indented under subclass 97. Instruments with two or more disks and generally with devices for setting them in playing position.

(1) Note. Some are coin-controlled.

100	With phonograph spindle:
	This subclass is indented under subclass 97. The motor of the music-box is utilized to drive a spindle for a phonograph.

[List of Patents for class 84 subclass 101]

101

Note-sheet type:

This subclass is indented under subclass 94.1. The selector is a note-sheet and usually operates star-wheels.

(1) Note. Sometimes the sheet controls the protrusion of pins beyond the surface of a cylinder.

[List of Patents for class 84 subclass 102]

102

Bars:

Automatic instruments having vibrating bars and not elsewhere classifiable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

2,	3, 6, 403, 404, and 405, for comparable inventions.

[List of Patents for class 84 subclass 103]

103

Bells:

Automatic instruments having vibrating bells and not elsewhere classifiable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

406,	and 407, for comparable inventions.

[List of Patents for class 84 subclass 104]

104

Drums:

Automatic instruments having vibrating drums and not elsewhere classifiable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

2,	3 and 6, for comparable inventions.

[List of Patents for class 84 subclass 105]

105

Outside players:

Instruments including a sheet or other selector, playing mechanism, and striker to act on the keys of a piano or organ and readily separable from the latter.

(1) Note. Some have a set of reeds or other sounders.

SEE OR SEARCH THIS CLASS, SUBCLASS:

24	through 82, for pneumatic-type pianos unless the construction is limited to an outside player.

106	Cylinder or disk:
	This subclass is indented under subclass 105. The selector is a cylinder or disk.

107	Electric or electropneumatic:
	This subclass is indented under subclass 105. The power is electromagnetic or electropneumatic.

108	Cabinet type:
	This subclass is indented under subclass 105. The instrument stands on the floor instead of on the piano.

109	Case connectors:
	This subclass is indented under subclass 108. Means for detachably holding the cabinet to the piano.

[List of Patents for class 84 subclass 110]

110

Pneumatic:

This subclass is indented under subclass 108. The playing mechanism includes pneumatics.

SEE OR SEARCH THIS CLASS, SUBCLASS:

24	through 82, for pneumatic-type pianos unless the construction is limited to an outside player.

111	Striker details:
	This subclass is indented under subclass 105. Details of the strikers or fingers that engage the piano-keys.

112	Constant power:
	This subclass is indented under subclass 105. The key-striker is operated from a constantly-moving source of power.

113	Electric control:
	This subclass is indented under subclass 112. The engagement between the source of power and the striker is controlled electrically.

114	Pneumatic control:
	This subclass is indented under subclass 112. The engagement between the source of power and the striker is controlled pneumatically.

[List of Patents for class 84 subclass 115]

115

Selectors:

The means for determining which notes of the piano, organ, etc., shall be sounded.

(1) Subject matter usually includes a tracker-bar, a perforated sheet, and driving means.

(2) Note. These features are shown in automatic telegraphs and in patents in many other subclasses of this class, and are sometimes claimed along with playing mechanism, such as in subclasses 24 through 52.

(3) Note. This subclass includes also details and optical or other attachments to the selector not otherwise classified.

SEE OR SEARCH THIS CLASS, SUBCLASS:

169,	for indicators.

[List of Patents for class 84 subclass 116]

116

Tracker-box location:

This subclass is indented under subclass 115. The invention is in the location or connection of the tracker-box.

SEE OR SEARCH THIS CLASS, SUBCLASS:

30,	for location of piano parts.

[List of Patents for class 84 subclass 117]

117

Mechanical fingers:

This subclass is indented under subclass 115. The note-sheet acts mechanically on movable fingers.

SEE OR SEARCH THIS CLASS, SUBCLASS:

147,	for electrical fingers.

118	Plurality of sheets:
	This subclass is indented under subclass 115. The instrument carries a plurality of note-sheets and means for driving them.

119	Synchronized:
	This subclass is indented under subclass 118. Two sheets are operated simultaneously.

120	Single tracker:
	This subclass is indented under subclass 118. The sheets are brought one at a time over a single tracker-bar and then driven separately.

121	Sheet not rolled:
	This subclass is indented under subclass 115. Various unusual forms of note-sheets and their feeding means, such as folding sheets, endless sheets, etc.

[List of Patents for class 84 subclass 122]

122

Winding and rewinding:

This subclass is indented under subclass 115. Inventions for moving a sheet not elsewhere classifiable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

92,	for simple friction-rolls.

123	With electric features:
	This subclass is indented under subclass 122. Electric mechanism is involved.

124	For two types of rolls:
	This subclass is indented under subclass 122. Means to carry rolls of different type or different compass one at a time.

125	Shifting gear and clutch:
	This subclass is indented under subclass 122. The mechanism for driving the sheet forward and back includes a shifting-gear and clutch.

126	Two clutches:
	This subclass is indented under subclass 122. The mechanism for driving the sheet forward and back includes two clutches.

127	Gears:
	This subclass is indented under subclass 122. The mechanism for driving the sheet forward and back includes gears.

[List of Patents for class 84 subclass 128]

128

Speed control:

This subclass is indented under subclass 122. Means for regulating the constant or momentary speed of the note sheet-tempo control.

SEE OR SEARCH THIS CLASS, SUBCLASS:

49,	for hand-controllers.

129	Roller and disk or cone:
	This subclass is indented under subclass 128. Patents including this specific variable friction-gear.

130	By wind supply:
	This subclass is indented under subclass 128. The speed is controlled by regulating the supply of wind to air-motors.

[List of Patents for class 84 subclass 131]

131

Compensation for diameter:

This subclass is indented under subclass 128. Means to keep the tempo constant as the diameter of the take-up roll increases.

SEE OR SEARCH CLASS:

242,	Winding, Tensioning, or Guiding, subclasses 540 -546.1 for drive mechanisms for convolute winding in general, particularly subclass 541 for a linear winding drive.

[List of Patents for class 84 subclass 132]

132

Feeding:

This subclass is indented under subclass 122. Miscellaneous devices for feeding a note-sheet forward. Includes some special take-up rolls.

SEE OR SEARCH THIS CLASS, SUBCLASS:

92,	for most types of simple feed-rolls.

SEE OR SEARCH CLASS:

226,	Advancing Material of Indeterminate Length, appropriate subclasses for methods of, and apparatus for, feeding material without utilizing the leading or trailing ends to effect movement of the material.
242,	Winding, Tensioning, or Guiding, subclasses 520 -548.4 for convolute winding in general.

133	Rewinding:
	This subclass is indented under subclass 122. Devices involved in rewinding, such as springs and weights.

[List of Patents for class 84 subclass 134]

134

Brakes:

This subclass is indented under subclass 122. Means to regulate the tension on the note-sheet.

SEE OR SEARCH CLASS:

242,	Winding, Tensioning, or Guiding, subclasses 410 -423.2 for tension control of running material in general.

135	Sheet pressers:
	This subclass is indented under subclass 122. Means to control the pressure of the note-sheet on the tracker-bar.

[List of Patents for class 84 subclass 136]

136

Registration:

This subclass is indented under subclass 122. Means to insure proper registration of the sheet perforations with the tracker-holes, usually automatic.

(1) Note. The tracker may be shifted, or one or both rolls; centering or guiding means.

SEE OR SEARCH CLASS:

226,	Advancing Material of Indeterminate Length, subclass 10 for means to sense and position material of indeterminate length.
242,	Winding, Tensioning, or Guiding, particularly subclasses 548 -548.4 and 615-615.4 for guides of web material in general.

137	Movable detector at edge:
	This subclass is indented under subclass 136. The shifting is controlled by one or more movable fingers or other detectors at the edge of the sheet.

138	Controlling shifter bellows:
	This subclass is indented under subclass 137. The shifting is done by bellows controlled by the detector.

139	Single detector:
	This subclass is indented under subclass 138. The shifting is controlled by a single detector.

[List of Patents for class 84 subclass 140]

140

Extra end holes:

This subclass is indented under subclass 122. The tracker has extra holes near its ends to control the shifting.

(1) The sheet may or may not have extra cooperating perforations.

141	Single end hole:
	This subclass is indented under subclass 140. There is only one extra hole to control the shifting in both directions.

142	Extra center holes:
	This subclass is indented under subclass 122. Holes near the middle of the tracker are vented by note perforations in the sheet.

143	Flange shifted:
	This subclass is indented under subclass 122. One flange (or both) is shifted on one or both rolls.

[List of Patents for class 84 subclass 144]

144

Hand operated:

This subclass is indented under subclass 122. The tracker-bar or some other part is shifted by hand.

(1) Note. This feature is found in many patents in preceding subclasses. The shift may be great enough to cause transposition.

[List of Patents for class 84 subclass 145]

145

Transposition only:

This subclass is indented under subclass 122. The relative shift of the tracker and sheet is through one or more semitones to cause a change of key.

SEE OR SEARCH THIS CLASS, SUBCLASS:

144,	for hand-operated parts.

[List of Patents for class 84 subclass 146]

146

Trackers and sheets:

This subclass is indented under subclass 115. Both the tracker and the sheet are modified.

(1) Note. Includes devices for violins, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

31,	and 32, for trackers.

[List of Patents for class 84 subclass 147]

147

Electric:

This subclass is indented under subclass 146. Electric circuits are controlled instead of pneumatic ducts.

SEE OR SEARCH THIS CLASS, SUBCLASS:

160,	for pneumato-electric tracker-bars.

148	For organs:
	This subclass is indented under subclass 146. Provision is made for control of stops.

149	Vertical:
	This subclass is indented under subclass 146. The tracker is vertical.

150	Playing on wind and rewind:
	This subclass is indented under subclass 146. The sheet has two sets of perforations, one set to be used as usual, the other to be used during rewinding.

151	Trackers:
	This subclass is indented under subclass 115. Special forms or construction of the tracker or attachments thereto.

[List of Patents for class 84 subclass 152]

152

Double scale:

This subclass is indented under subclass 151. Especially to allow the use of sixty-five or eighty-eight note-sheets at will. There are covers or other means to close either set of ducts.

(1) Note. In the trackers of subclass 31, both rows are in use together.

153	Trackers rigidly connected:
	This subclass is indented under subclass 152. The two rows of holes are in the same bar or in bars fixed together.

154	Pivotally mounted:
	This subclass is indented under subclass 153. The bar is pivoted.

155	With slide valves:
	This subclass is indented under subclass 153. Slide-valves determine which row shall be used.

156	Duct closers:
	This subclass is indented under subclass 151. Means to close a few ducts at the end of a row if a narrow sheet is used or to close all during rewinding or skipping.

[List of Patents for class 84 subclass 157]

157

Modified for expression:

This subclass is indented under subclass 151. To avoid mechanically accurate playing.

SEE OR SEARCH THIS CLASS, SUBCLASS:

47,	for systematic variations.

158	Metal:
	This subclass is indented under subclass 151. The tracker-bar is of metal.

159	Extensible:
	This subclass is indented under subclass 151. The bar is adjustable in length.

160	Pneumato-electric:
	This subclass is indented under subclass 151. The tracker-bar has ducts admitting air to pouches or small bellows that operate electric switches.

161	Note sheets:
	This subclass is indented under subclass 115. Improvements in the sheet, its material, construction, perforations, or attachments.

162	Ends and joints:
	This subclass is indented under subclass 161. Improvements at the free end of the sheet or in means for joining two ends together.

163	Overlapping holes:
	This subclass is indented under subclass 161. Perforations for two successive notes overlap to produce a legato effect or for accent, etc.

[List of Patents for class 84 subclass 164]

164

With expression and tempo marks:

This subclass is indented under subclass 161. The sheet bears lines or other marks to indicate the proper expression or tempo.

SEE OR SEARCH THIS CLASS, SUBCLASS:

49,	and 169, for cooperating parts.

165	With marks for voice:
	This subclass is indented under subclass 161. The sheet bears words or marks to indicate a vocal part.

[List of Patents for class 84 subclass 166]

166

With projections:

This subclass is indented under subclass 161. The sheet or disk has projections, sometimes adjustable, instead of perforations.

SEE OR SEARCH THIS CLASS, SUBCLASS:

97	through 100, for disk type.

[List of Patents for class 84 subclass 167]

167

Key locks:

Means to prevent the keys from moving as the piano is played.

SEE OR SEARCH THIS CLASS, SUBCLASS:

74,	for devices to lock piano keys.

168	Couplers:
	Means, usually pneumatic, for sounding two notes together, especially octaves.

169	Indicators:
	Indicators of various kinds connected to automatic instruments.

170	Combined:
	This subclass is indented under subclass 1. Instruments having sounders belonging to two of the four groups, such as a piano or organ with bell, bar, or drum attachment.

171	Electric:
	This subclass is indented under subclass 170. Combined instruments employing electric circuits.

172	Piano and organ:
	This subclass is indented under subclass 170. Combination of a piano and reed (or pipe) organ, often with means for disconnecting one set of sounders from the keys.

[List of Patents for class 84 subclass 173]

173

Stringed:

This subclass is indented under subclass 1. Miscellaneous stringed instruments and devices relating thereto not classifiable elsewhere.

(1) Note. Includes Aeolian harps.

SEE OR SEARCH THIS CLASS, SUBCLASS:

600	through 746, for electrical musical tone generation.

[List of Patents for class 84 subclass 174]

174

Pianos:

This subclass is indented under subclass 173. Miscellaneous patents showing pianos of unusual shape or claiming several features or not elsewhere classifiable.

(1) Note. Many features of a piano are common to other instruments and should be searched for in appropriate subclasses of automatic, stringed, or wind instruments, rigid vibrators, or general features in this class.

SEE OR SEARCH THIS CLASS, SUBCLASS:

170	through 172, for pianos having bells or other sounding attachments.

175	Duplex:
	This subclass is indented under subclass 174. Two sets of strings and sometimes two keyboards.

176	Separable:
	This subclass is indented under subclass 174. The piano is conveniently separable into parts, especially for ease of transportation.

[List of Patents for class 84 subclass 177]

177

Cases:

This subclass is indented under subclass 174. The improvements are in the case.

SEE OR SEARCH THIS CLASS, SUBCLASS:

75,	and 80-82, for cases for pneumatic pianos.
430,	and 431, for key-beds or key-bottoms.

178	Fall boards and desks:
	This subclass is indented under subclass 177. The improvements related to both the music-desk and the fall-board over the keys.

[List of Patents for class 84 subclass 179]

179

Fall boards:

This subclass is indented under subclass 177. The improvements relate to the fall-board alone.

(1) Note. Includes devices for equalizing the movements of the ends.

180	Music desks or racks:
	This subclass is indented under subclass 177. The improvements relate to the music desk or rack.

181	Music receptacles:
	This subclass is indented under subclass 177. The case has pockets or shelves for holding music or music-rolls.

[List of Patents for class 84 subclass 182]

182

Swells:

This subclass is indented under subclass 177. The case has shutters or slides to control the escape of sound.

SEE OR SEARCH THIS CLASS, SUBCLASS:

189,	346 and 372, for resonance devices.

[List of Patents for class 84 subclass 183]

183

Protectors:

This subclass is indented under subclass 177. Means to protect the case, especially around the pedals.

SEE OR SEARCH THIS CLASS, SUBCLASS:

177,	for piano cases.

184	Frames, string plate and sounding boards:
	This subclass is indented under subclass 174. All three parts are modified.

185	Frames and string plates:
	This subclass is indented under subclass 174. Both parts are modified.

186.1	Frames:
	This subclass is indented under subclass 174. Subject matter having improvements in the frames or backs of wood or metal.

186.2	Wrest planks:
	This subclass is indented under subclass 186.1. Subject matter having improvements in the wrest planks.

187	String plates and sounding boards:
	This subclass is indented under subclass 174. Improvements in the two features.

[List of Patents for class 84 subclass 188]

188

String plates:

This subclass is indented under subclass 174. Improvements in the metal plate.

SEE OR SEARCH THIS CLASS, SUBCLASS:

200,	for tuning devices.
208,	through 215, for bridges.

[List of Patents for class 84 subclass 189]

189

Resonance devices:

This subclass is indented under subclass 174. Devices to communicate to the air vibrations due to the strings or to modify them in loudness or quality.

(1) Note. These devices do not directly affect the movement of the strings.

(2) Note. Some expression devices (subclass 216, etc.) might come under this broad definition, but most of them affect the amplitude or form of vibration of the strings and are under control of the player.

SEE OR SEARCH THIS CLASS, SUBCLASS:

182,	for swells.
224,	for auxiliary strikers.
234,	for harmonic dampers.
294,	for resonance devices.
295,	for auxiliary strings.

190	Supports or platforms:
	This subclass is indented under subclass 189. Resonant supports on which the instrument may stand.

191	Insulators:
	This subclass is indented under subclass 189. Devices supposed to prevent the wasteful transmission of energy, such as to the floor.

192	Sounding boards:
	This subclass is indented under subclass 189. The principal means by which the energy of the vibrating string is communicated to the air.

193	Materials:
	This subclass is indented under subclass 192. Sounding-boards made of unusual material, especially metal.

194	Multiple:
	This subclass is indented under subclass 192. Boards additional to the main sounding board and hollow bodies analogous to a violin.

195	Ribbing:
	This subclass is indented under subclass 192. Modifications in the location, arrangement, or structure of the ribs.

[List of Patents for class 84 subclass 196]

196

Crowning devices:

This subclass is indented under subclass 192. Means to maintain the board in an arched form.

SEE OR SEARCH THIS CLASS, SUBCLASS:

184,	through 188, for frames, string plates, and sounding boards.

197	Stringing:
	This subclass is indented under subclass 174. Modifications in the location or arrangement of the strings.

198	Auxiliary strings:
	This subclass is indented under subclass 197. Extra strings or extensions furnishing unisons or harmonics that may be struck by the hammer or may vibrate sympathetically.

[List of Patents for class 84 subclass 199]

199

Strings:

This subclass is indented under subclass 174. Special material or construction of the strings.

SEE OR SEARCH CLASS:

57,	Textiles: Spinning, Twisting, and Twining, subclasses 210 through 235for spirally wrapped strands of general application.

[List of Patents for class 84 subclass 200]

200

Tuning devices:

This subclass is indented under subclass 174. Miscellaneous devices for straining the strings.

SEE OR SEARCH THIS CLASS, SUBCLASS:

304,	for tuning pegs.
305,	for friction increasers.
306,	for worm gear.

201	Simple pin:
	This subclass is indented under subclass 200. Integral pins.

202	Locking devices:
	This subclass is indented under subclass 200. Pins with means for locking them or for increasing the friction.

203	Involving two pins:
	This subclass is indented under subclass 202. Devices that involve two pins.

204	Worm gear:
	This subclass is indented under subclass 200. Devices that involve a worm-gear.

205	Direct pull:
	This subclass is indented under subclass 200. The string is pulled directly, not wound on a pin.

206	With push piece:
	This subclass is indented under subclass 200. The string is fastened to a movable block.

207	With lever:
	This subclass is indented under subclass 200. The string is fastened to a lever.

208	Transverse pressure:
	This subclass is indented under subclass 200. The tuning-pin deflects the string from a straight line.

[List of Patents for class 84 subclass 209]

209

Bridges:

This subclass is indented under subclass 174. Patents for bridges not belonging in the subclasses below.

(1) Note. The vibrating length of the string is determined by its bearing on the two bridges, one on the sounding-board and the other usually on the wrest-plank or on the string-plate. If on the plate, it is sometimes distinguished as the "scale rib". If the two bridges are not on the same side of the string, the one near the hammer-line may be called "inverted". Often the hammer-stroke tends to lift the string from the bridge on the plank, so in some early pianos a sort of screw-eye called an "a gaffe" was used, while in later times many sorts of clamps or holders have been devised to hold the strings on their bridges, and confusing names have been given them.

210	Inverted:
	This subclass is indented under subclass 209. See Note to subclass 209.

211	Agraffes:
	This subclass is indented under subclass 209. See Note to subclass 209.

212	On sounding board:
	This subclass is indented under subclass 209. The principal bridge, usually long, curved and near the hitch-pins.

213	With string holders:
	This subclass is indented under subclass 212. Means on the bridge for clamping or holding the strings in place.

214	String clamps or holders:
	This subclass is indented under subclass 209. Means for clamping or holding a string not on the main bridge.

215	Depressing bars:
	This subclass is indented under subclass 209. Bars for holding the strings firmly against the bridge on the string-plate; sometimes called "capo-tasto bars".

[List of Patents for class 84 subclass 216]

216

Expression devices:

This subclass is indented under subclass 174. Various means for changing the quality of tone of a piano.

(1) Note. See (2) Note to this class, subclass 189.

[List of Patents for class 84 subclass 217]

217

Dampers lifted:

This subclass is indented under subclass 216. Many or all of the dampers are lifted, so that their strings may enter into sympathetic vibration.

(1) Note. This is the ordinary "forte" arrangement controlled by the damper-pedal.

218	Dampers held:
	This subclass is indented under subclass 216. The sustaining or third pedal device to retain only those dampers which are raised by the keys at the time the damper is applied.

[List of Patents for class 84 subclass 219]

219

Pianissimo devices:

This subclass is indented under subclass 216. Devices to soften the blow of the hammer or produce a softer sound.

(1) Note. Such devices may render the piano silent.

SEE OR SEARCH THIS CLASS, SUBCLASS:

35	through 38, for shifted hammer rest-rails.

[List of Patents for class 84 subclass 220]

220

Curtain type:

This subclass is indented under subclass 219. A curtain is interposed between the hammer and the strings.

(1) Note. Called "celeste" in old patents.

221	Hammer stroke shortened:
	This subclass is indented under subclass 219. This is the common modern construction.

222	Lost-motion preventers:
	This subclass is indented under subclass 221. Devices to prevent a gap in the connections between the keys and hammer-butts.

223	In grand actions:
	This subclass is indented under subclass 222. Similar devices adapted to grand-actions.

[List of Patents for class 84 subclass 224]

224

Auxiliary strikers:

This subclass is indented under subclass 216. Small weighted tongues in the path of the hammers to strike the strings.

(1) Note. Sometimes called a "mandolin attachment".

[List of Patents for class 84 subclass 225]

225

Pedal mechanism:

This subclass is indented under subclass 216. Means to operate the expression devices and details thereof.

SEE OR SEARCH THIS CLASS, SUBCLASS:

216	through 233, for expression devices.

226	Locks:
	This subclass is indented under subclass 225. Means to hold the mechanism in operated position.

227	Spring fulcrum:
	This subclass is indented under subclass 225. One of the levers is carried on a spring instead of on bearings.

228	Bearings:
	This subclass is indented under subclass 225. Bearings specially adapted for use in this mechanism.

229	Pedals:
	This subclass is indented under subclass 225. The exposed levers of the mechanism.

[List of Patents for class 84 subclass 230]

230

Auxiliary:

This subclass is indented under subclass 229. Pedals supplementary to the usual pedals, generally for children’s use.

SEE OR SEARCH THIS CLASS, SUBCLASS:

358,	for similar devices.

SEE OR SEARCH CLASS:

74,	Machine Element or Mechanism, subclasses 512 through 514and 560-563 for similar devices.

231	Pedal carried:
	This subclass is indented under subclass 230. The supplementary part is clamped to the pedal.

232	With footrest:
	This subclass is indented under subclass 230. The supplementary part is carried on a footstool.

[List of Patents for class 84 subclass 233]

233

Mouse guards:

This subclass is indented under subclass 225. Devices to prevent the entrance of mice through the pedal-openings.

SEE OR SEARCH THIS CLASS, SUBCLASS:

353,	for modifications of the case around the pedals.

234	Harmonic dampers:
	This subclass is indented under subclass 174. Means to touch a string at the middle or other nodal point, so causing it to produce a harmonic tone.

[List of Patents for class 84 subclass 235]

235

Couplers:

This subclass is indented under subclass 174. Devices to operate two hammers from a single key.

SEE OR SEARCH THIS CLASS, SUBCLASS:

373,	for devices causing two notes.
424,	for keyboards like those of a pipe organ and couplers therefore.

[List of Patents for class 84 subclass 236]

236

Hammers actions:

This subclass is indented under subclass 174. Patents covering the parts between the key and the strings, usually called collectively, a "piano-action".

(1) Note. The keys are not treated as parts of the action.

(2) Note. The title distinguishes from the pedal-actions of an ordinary piano.

SEE OR SEARCH THIS CLASS, SUBCLASS:

323,	and 324, for simple actions.
423,	for keyboards.
426,	for pedals to operate the hammers.

237	Horizontal:
	This subclass is indented under subclass 236. These actions are mostly for the old type of square pianos.

238	Down striking:
	This subclass is indented under subclass 237. The hammers strike downward instead of upward.

[List of Patents for class 84 subclass 239]

239

Grand:

This subclass is indented under subclass 237. The modern standard action of the Herz-Erard type, in which the jack and repetition-lever both engage the nose on the hammer.

SEE OR SEARCH THIS CLASS, SUBCLASS:

237,	for other types of hammer action.

240	Upright:
	This subclass is indented under subclass 236. Miscellaneous types of action for pianos having strings in a nearly vertical plane.

241	Jack serving as retractor:
	This subclass is indented under subclass 240. The jack positively retracts the hammer, so that a bridle is not needed.

242	Standard type:
	This subclass is indented under subclass 240. The common action, each unit of it including a wippen carrying a jack, a damper-spoon, a back-check, and a bridle-wire.

243	Details:
	This subclass is indented under subclass 236. Patents for features not elsewhere classifiable.

244	Power-operated hammers:
	This subclass is indented under subclass 243. The hammer is driven by power controlled by the key.

[List of Patents for class 84 subclass 245]

245

Sostenuto:

This subclass is indented under subclass 244. Devices for producing sustained tone instead of the ordinary evanescent one.

SEE OR SEARCH THIS CLASS, SUBCLASS:

105	through 114, for outside players.

246	Electric striker:
	This subclass is indented under subclass 244. The striker is moved by an electromagnet.

247	Jack constantly controlled:
	This subclass is indented under subclass 243. Actions designed to give the player constant control of the hammer, such as clavichord players had.

248	Inverted jack:
	This subclass is indented under subclass 243. The jack is pivoted at its top and escapes at the bottom.

249	Jointed jack:
	This subclass is indented under subclass 243. The jack is pivoted at top and bottom and jointed near the middle—a kind of reversed toggle.

250	Action frames:
	This subclass is indented under subclass 243. Frames carrying the parts of the action and the rails of the expression devices.

251	Flanges and joints:
	This subclass is indented under subclass 243. The hingelike parts by which the moving parts are attached to one another or to the rails.

252	Continuous:
	This subclass is indented under subclass 251. Several flange units are integrally connected together.

253	Checks:
	This subclass is indented under subclass 243. Devices for catching the hammer and holding it at rest after it has recoiled from the string.

[List of Patents for class 84 subclass 254]

254

Hammer heads:

This subclass is indented under subclass 243. Improvements in the striking parts of the hammer and in hammer-felts.

SEE OR SEARCH CLASS:

144,	Woodworking, subclass 29 for piano-hammer felting.

[List of Patents for class 84 subclass 255]

255

Damper heads and stems:

This subclass is indented under subclass 243. Improvements in damper-heads.

(1) Note. Dampers are shown in numerous patents for pianos or piano-actions or automatic pianos or stringed instruments.

[List of Patents for class 84 subclass 256]

256

Bowed or violin pianos:

This subclass is indented under subclass 174. Instruments having many strings excited by friction; "violin-pianos".

SEE OR SEARCH THIS CLASS, SUBCLASS:

325,	for bowing mechanisms.
326,	for keys operating fretting or fingering means.

[List of Patents for class 84 subclass 257]

257

With belt bow:

This subclass is indented under subclass 256. In these the exciting means is a belt.

SEE OR SEARCH THIS CLASS, SUBCLASS:

325,	for bowing mechanisms.
326,	for keys operating fretting or fingering means.

[List of Patents for class 84 subclass 258]

258

Plectrum:

This subclass is indented under subclass 174. The strings are picked, somewhat as in the old harpsichords.

SEE OR SEARCH THIS CLASS, SUBCLASS:

320,	for picking devices.

[List of Patents for class 84 subclass 263]

263

Combined:

This subclass is indented under subclass 173. Instruments having two sets of strings, often on different necks or on opposite sides of the body.

(1) Note. The following subclasses--264 to 289--are intended only for features specific to the instrument named. If the feature is applicable to instruments of two kinds, as a harp and violin, the patent is classified under this class, subclass 290, and indented subclasses.

264	Harps:
	This subclass is indented under subclass 173. Theses have many strings of graduated length stretched on a frame consisting of the body, neck, and pillar; the strings are exposed on both sides to the player’s hands.

265	Bodies:
	This subclass is indented under subclass 264. Patents for harps where the improvement is in the body only.

266	Erard action:
	This subclass is indented under subclass 264. Patents for improvements in the mechanism by which the pitch of the strings is changed one or two semitones.

267	Guitars:
	This subclass is indented under subclass 173. Patents showing a few strings stretched along a fretted neck, unless clearly belonging to a subclass below.

268	Mandolins:
	This subclass is indented under subclass 173. The patents herein relate almost exclusively to the body.

[List of Patents for class 84 subclass 269]

269

Banjos:

This subclass is indented under subclass 173. Instruments having a flexible head and a neck.

SEE OR SEARCH THIS CLASS, SUBCLASS:

193,	for metal heads.

[List of Patents for class 84 subclass 270]

270

Resonance devices:

This subclass is indented under subclass 269. Means to change the quality of the banjo-tones by an attachment or especially by partly-closed air-cavities.

SEE OR SEARCH THIS CLASS, SUBCLASS:

294,	for resonance devices.

271	Closed back:
	This subclass is indented under subclass 270. Banjos having the back partly or wholly closed.

272	Two rings:
	This subclass is indented under subclass 270. Banjos in which the head is stretched over two concentric rings.

[List of Patents for class 84 subclass 273]

273

Mutes:

This subclass is indented under subclass 270. A mute or damper for pressing on the head.

SEE OR SEARCH THIS CLASS, SUBCLASS:

310,	for violin-mutes.

274	Violins:
	This subclass is indented under subclass 173. Improvements not likely to be applicable to any instruments other than those of the violin family and not belonging in subclasses below; also patents involving two specific features.

275	Bodies:
	This subclass is indented under subclass 274. Modifications in the body of a violin.

276	Bass bars:
	This subclass is indented under subclass 275. Changes in the bass-bar.

277	Sound posts:
	This subclass is indented under subclass 275. Changes in the sound-post.

278	Combined chin rest and support:
	This subclass is indented under subclass 274. Patents covering a combination of the two features.

279	Chin rests:
	This subclass is indented under subclass 274. Changes in chin-rests.

280	Supports:
	This subclass is indented under subclass 274. Changes in supports for a violin or violoncello.

281	Positioning devices:
	This subclass is indented under subclass 274. Means for holding the player’s arm and the violin in proper position.

282	Bows:
	This subclass is indented under subclass 274. Modifications in the construction of violin-bows.

283	Bow guides:
	This subclass is indented under subclass 274. Devices for guiding the bow in proper relation to the strings.

284	Dulcimers:
	This subclass is indented under subclass 173. Strings stretched over a sounding-board to be struck by hammers in the player’s hands.

[List of Patents for class 84 subclass 285]

285

Zithers:

This subclass is indented under subclass 173. Strings stretched over a sounding-board in position to be picked; the strings are often divided into melody-strings and accompaniment-strings, the former sometimes lying over a finger-board.

SEE OR SEARCH THIS CLASS, SUBCLASS:

290	through 329, for other features associated with stringed instruments.

286	Chord selectors:
	This subclass is indented under subclass 285. Instruments, usually of the zither type, in which strings are sounded in chord groups, specifically by multiple picks or hammers fixed on a bar and operating simultaneously.

[List of Patents for class 84 subclass 287]

287

Damper-bar type:

This subclass is indented under subclass 286. The dampers mute all strings except those needed for the desired chord.

(1) Note. This subclass covers the original "auto-harp".

288	Dampers independent:
	This subclass is indented under subclass 287. These dampers may be operated by hand or by a tune-sheet.

289	Guard-plate type:
	This subclass is indented under subclass 286. The plate has holes through which a pick strikes strings that furnish a chord.

290	Details:
	This subclass is indented under subclass 173. Includes features not practically limited to a single one of the well-known types of stringed instruments in the subclasses above.

[List of Patents for class 84 subclass 291]

291

Bodies:

This subclass is indented under subclass 290. Hollow resonance-bodies for instruments having a neck.

(1) Note. For bodies special to any one type of instrument see the subclass relating to such instrument.

292	Metal:
	This subclass is indented under subclass 291. Bodies of metal.

293	Necks:
	This subclass is indented under subclass 290. Patents covering the construction of the neck or its connection or inclination to the body.

[List of Patents for class 84 subclass 294]

294

Resonance devices:

This subclass is indented under subclass 290. Devices for changing the quality of tone of an instrument, as air-cavities, extra sounding-boards, sympathetically-vibrating parts, or small membranes.

SEE OR SEARCH THIS CLASS, SUBCLASS:

234,	for harmonic dampers.

295	Auxiliary strings:
	This subclass is indented under subclass 294. Extra strings inside or outside of the body.

[List of Patents for class 84 subclass 296]

296

With diaphragm:

This subclass is indented under subclass 294. The string sets a diaphragm in vibration.

(1) Note. A horn is usually shown.

[List of Patents for class 84 subclass 297]

297

Strings and fastenings:

This subclass is indented under subclass 290. Improvements in the string and the means for fastening it.

(1) Note. In this and the next six subclasses, there are many devices for correcting the lengths of strings or tuning them or changing the pressure on the bridge.

298	Guitar bridges:
	This subclass is indented under subclass 297. These usually hold the end of the string and a separate tailpiece is not necessary.

299	Guitar bridges with tailpieces:
	This subclass is indented under subclass 297. Both a bridge and a tailpiece are used.

300	Banjo tailpieces:
	This subclass is indented under subclass 297. Tailpieces specially adapted to a banjo.

301	Mandolin tailpieces:
	This subclass is indented under subclass 297. Tailpieces specially adapted to a mandolin.

302	Violin tailpieces:
	This subclass is indented under subclass 297. Tailpieces specially adapted to a violin.

303	Spools:
	This subclass is indented under subclass 297. Devices for winding up the surplus length of string.

304	Tuning pegs:
	This subclass is indented under subclass 297. Patents mostly for simple tuning-pegs, sometimes with means for gripping the string.

305	Friction increasers:
	This subclass is indented under subclass 304. Means for holding the peg more tightly than usual.

[List of Patents for class 84 subclass 306]

306

Worm gear:

This subclass is indented under subclass 297. Tuning devices having a worm-gear.

(1) Note. Sometimes called "machine head" or "patent head".

307	Bridges:
	This subclass is indented under subclass 290. Bridges not limited to the following subclasses.

308	Banjo:
	This subclass is indented under subclass 307. Bridges specially adapted to a banjo-head.

309	Violin:
	This subclass is indented under subclass 307. Bridges specially adapted to a violin.

310	Violin mutes:
	This subclass is indented under subclass 307. Devices to be applied to violin-bridges; sordines.

311	Attached:
	This subclass is indented under subclass 310. The mute is attached to the violin and can be readily shifted into operative position.

312	Tunings:
	This subclass is indented under subclass 290. Unusual tunings or arrangement of chord groups, particularly in zithers.

313	Tremolo devices:
	This subclass is indented under subclass 290. Device for producing amplitude modulation.

314	Finger boards and frets:
	This subclass is indented under subclass 290. Includes the structure of the finger-board, markings on it, frets, and nuts.

[List of Patents for class 84 subclass 315]

315

Fingering devices:

This subclass is indented under subclass 290. Devices to shorten or stop a string at proper points, as a guitar player does with his finger.

SEE OR SEARCH THIS CLASS, SUBCLASS:

326,	for devices with keyboard.

[List of Patents for class 84 subclass 316]

316

For semitone:

This subclass is indented under subclass 315. Devices to sharp or flat a note, so as to change the key.

SEE OR SEARCH THIS CLASS, SUBCLASS:

266,	for mechanisms that change the pitch of strings.

[List of Patents for class 84 subclass 317]

317

For chords:

This subclass is indented under subclass 315. Devices to finger several strings at once, so that a chord may be produced.

SEE OR SEARCH THIS CLASS, SUBCLASS:

443,	for chord players.

318	Capo tastos:
	This subclass is indented under subclass 317. Clamps to shorten all the strings of a guitar or to perform an equivalent operation on other instruments.

319	Stopping fingers or blocks:
	This subclass is indented under subclass 315. Devices held by the player to stop one or more strings, such as on the Hawaiian guitar.

[List of Patents for class 84 subclass 320]

320

Picking devices:

This subclass is indented under subclass 290. Miscellaneous devices for picking, plucking, or pulling strings.

(1) Note. This subclass and the next two subclasses deal with devices for "playing" or exciting the strings.

SEE OR SEARCH THIS CLASS, SUBCLASS:

8,	258, 404, and 409, for similar devices.

321	Picks on reciprocating carriage:
	This subclass is indented under subclass 320. All the picks are reciprocated at once.

322	Hand or finger picks:
	This subclass is indented under subclass 320. Simple picks held by the player.

[List of Patents for class 84 subclass 323]

323

Hammer mechanism:

This subclass is indented under subclass 290. Patents for simple actions adapted to a zither and usually downstriking.

(1) Note. The instrument is often called a "keyed zither".

SEE OR SEARCH THIS CLASS, SUBCLASS:

237,	238 and 240, for hammer actions.
246,	for electrically operated hammers.

[List of Patents for class 84 subclass 324]

324

Spring-shank hammer:

This subclass is indented under subclass 323. To produce a vibrato or tremolo effect.

SEE OR SEARCH THIS CLASS, SUBCLASS:

284,	for hand-hammers.

[List of Patents for class 84 subclass 325]

325

Bowing mechanism:

This subclass is indented under subclass 290. For violins or zithers.

SEE OR SEARCH THIS CLASS, SUBCLASS:

10,	and 11, for automatic violins.
282,	for ordinary violin-bows.

[List of Patents for class 84 subclass 326]

326

With keyboard:

This subclass is indented under subclass 325. The keys operate fretting or fingering means, so that only a few strings are needed.

(1) Note. The complete instrument is usually called a "piano-violin".

SEE OR SEARCH THIS CLASS, SUBCLASS:

256,	and 257, for instruments having many open strings.

[List of Patents for class 84 subclass 327]

327

Instrument supports:

This subclass is indented under subclass 290. Devices for supporting or positioning guitars, etc., during playing.

SEE OR SEARCH THIS CLASS, SUBCLASS:

278,	and 280, for chin rests and supports.

[List of Patents for class 84 subclass 328]

328

Arm, hand, or finger rests:

This subclass is indented under subclass 290. Means to support the player’s hand in proper relation to the instrument.

SEE OR SEARCH THIS CLASS, SUBCLASS:

469,	for armrest rail.

329	Article holders:
	This subclass is indented under subclass 290. Devices attached to an instrument to hold an article, such as a pick or a cake of rosin.

[List of Patents for class 84 subclass 330]

330

Wind:

This subclass is indented under subclass 1. Miscellaneous wind instruments and some details not elsewhere classifiable; also combinations of pipes and reeds.

(1) Note. The patents of this group may be classed as pipe organs, reed organs, minor reed instruments, orchestral wood winds, and brasses. The first two have many features in common; but they differ so much in size and consequently in details that a parallel classification has been made. Search should ordinarily be made in the proper subclasses of both types and sometimes in "Automatics". Wind-supply devices and pressure-regulators are mostly classed in Class 60, Power Plants, and Class 417, Pumps.

331	Pipe organs:
	This subclass is indented under subclass 330. Patents covering the whole organization or several details or features not elsewhere classifiable.

[List of Patents for class 84 subclass 332]

332

Actions:

This subclass is indented under subclass 331. Pipe-organ actions not belonging to a specific subclass.

(1) Note. The speaking of an organ-pipe is usually controlled by the joint operation of devices actuated or controlled, respectively, by a key and a stop. These devices (excluding the keys) are collectively known as the "action". These actions and the corresponding wind-chests are of three types: (1) the older, in which the top of the wind-chest has as many grooves with pallets to control them as there are keys and as many perforated slides crossing the grooves as there are speaking-stops; (2) the type in which there are as many stop-chambers as stops, each carrying a series or "register" of pipes and each controlled by a valve or "ventil", every pipe having its own valve controlled by a key, and (3) the type in which all the pipes stand on a common or "universal" wind-chest and each pipe has its own valve, which is jointly controlled by a key and a draw-stop. In all three types the controlling means may be mechanical, electrical, pneumatic, or electropneumatic. For details of such means see this class, subclass 335, and following subclasses. Patents for combinations of the first type are in this subclass.

333	Stop chambers:
	This subclass is indented under subclass 332. Combinations belonging to type 2 of the Note above.

334	Single chamber:
	This subclass is indented under subclass 332. Combinations belonging to type 3 of the above Note.

335	Pneumatic details:
	This subclass is indented under subclass 332. The invention is essentially embodied in one pneumatic and valve.

336	Membrane valve:
	This subclass is indented under subclass 335. A diaphragm serves as a valve.

[List of Patents for class 84 subclass 337]

337

Electric:

This subclass is indented under subclass 332. Includes patents for complete organizations and for electric details; also inertia-controlled circuit-closers.

SEE OR SEARCH THIS CLASS, SUBCLASS:

341,	for electric means for coupling parts of an organ.

338	Electropneumatic:
	This subclass is indented under subclass 332. Includes organizations in which electromagnetic valves control pneumatics; also pneumato-electric actions in which pneumatics control switches in the circuits of electromagnets.

339	Details:
	This subclass is indented under subclass 338. Includes units or details of such actions.

340	Pneumatic:
	Pneumatic means for coupling parts of an organ.

[List of Patents for class 84 subclass 341]

341

Electric:

Electric means for coupling parts of an organ.

(1) Note. In pneumatic and electric organ-actions, there is no sharp line of distinction between couplers and stop-actions, and in some modern constructions the old nomenclature is inapt.

SEE OR SEARCH THIS CLASS, SUBCLASS:

235,	for couplers.
337,	for electric details of pipe organs; also inertia-controlled circuit closers.
338,	for electro pneumatic pipe organs; also pneumo-electric actions.
351	through 374, particularly subclass 373 for a simple type of rock-shaft for octave-couplers common to reed organs.
424,	for means for coupling two keyboards together.

[List of Patents for class 84 subclass 342]

342

Key valves:

This subclass is indented under subclass 332. Details of the pallet or other key-operated valve.

SEE OR SEARCH THIS CLASS, SUBCLASS:

368,	for key-operated valves.

[List of Patents for class 84 subclass 343]

343

Stop actions:

This subclass is indented under subclass 332. Details of the draw-stops or stop-keys, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

331	through 334, for the complete stop-action.

344	Combination:
	This subclass is indented under subclass 343. A single pedal or button brings on a plurality of stops selected by the organ builder.

[List of Patents for class 84 subclass 345]

345

Adjustable:

This subclass is indented under subclass 344. A single pedal or button brings on a plurality of stops selected by the player.

(1) Note. The last two subclasses include organs of all three types described above and actions of the several varieties, also crescendo and sforzando devices.

346	Swells:
	This subclass is indented under subclass 331. Patents relating to swell-shutters and means for operating them.

347	Electropneumatic:
	This subclass is indented under subclass 346. The shutters are operated or controlled by an electropneumatic action.

[List of Patents for class 84 subclass 348]

348

Valve tremolos:

This subclass is indented under subclass 331. A vibrating valve produces an irregularity in the flow of air and so in loudness of the sound.

SEE OR SEARCH THIS CLASS, SUBCLASS:

374,	for fan tremolos.

349	Pipes:
	This subclass is indented under subclass 331. The improvement is embodied in one individual pipe.

350	Reed:
	This subclass is indented under subclass 349. The improvement is embodied in one individual reed-pipe, which usually has a beating-reed.

[List of Patents for class 84 subclass 351]

351

Reed organs:

This subclass is indented under subclass 330. Patents for the general construction of a reed-organ.

(1) Note. Familiar trade-names are "harmonium, melodeon, cabinet-organ". The reeds are usually free.

(2) Note. While most of these constructions are obsolete, these patents should be searched for features or details not clearly found in the subclasses below.

352	Cases:
	This subclass is indented under subclass 351. Patents for features of the case.

[List of Patents for class 84 subclass 353]

353

Pedals:

Patents wherein there is some modification of the case around the pedals.

SEE OR SEARCH THIS CLASS, SUBCLASS:

233,	for mouse-guards.
357,	for other organ-pedals.

354	Folding:
	This subclass is indented under subclass 351. Collapsible or "suitcase" organs.

[List of Patents for class 84 subclass 355]

355

Wind-supply devices:

This subclass is indented under subclass 351. Includes pumpers and sometimes electric motors.

SEE OR SEARCH THIS CLASS, SUBCLASS:

70,	for other wind supply-devices.

356	Pressure and exhaust:
	This subclass is indented under subclass 355. Instruments involving both exhaust and pressure mechanisms.

[List of Patents for class 84 subclass 357]

357

Pedals:

This subclass is indented under subclass 355. Includes pedals and connections to the bellows.

SEE OR SEARCH THIS CLASS, SUBCLASS:

353,	for case modification.

[List of Patents for class 84 subclass 358]

358

Auxiliary:

This subclass is indented under subclass 357. For the use of children.

SEE OR SEARCH THIS CLASS, SUBCLASS:

230	through 232, for supplementary pedals for children.

[List of Patents for class 84 subclass 359]

359

Distribution:

This subclass is indented under subclass 355. Includes parts between the pumpers and the actions.

SEE OR SEARCH CLASS:

417,	Pumps, subclasses 279+ for pumps having condition responsive control of the fluid handled by the pump.

360	Reed boards:
	This subclass is indented under subclass 351. Boards in which the reed-cells are formed.

361	With qualifying tubes:
	This subclass is indented under subclass 360. Tubes each communicating with one or a very few reed-cells.

362	With resonance chamber:
	This subclass is indented under subclass 360. Chambers each communicating with many cells.

363	Reeds:
	This subclass is indented under subclass 351. Patents where the improvement is in the reed alone.

364	With tuning means:
	This subclass is indented under subclass 363. Means for tuning the reed are included.

365	Key actions:
	This subclass is indented under subclass 351. Modifications in the parts of the action operated or controlled by the keys; devices to start the tongue in prompt vibration.

366	Pedal:
	This subclass is indented under subclass 365. Actions connected to a pedal-keyboard.

367	Pneumatic:
	This subclass is indented under subclass 365. Patents including a pneumatic in the key action.

[List of Patents for class 84 subclass 368]

368

Pallets:

This subclass is indented under subclass 365. Key-operated valves.

SEE OR SEARCH THIS CLASS, SUBCLASS:

342,	for other key-operated valves.

369	Stop actions:
	This subclass is indented under subclass 351. Patents relating to draw-stops and to the mutes and other parts of the action operated by the stops.

370	Combination:
	This subclass is indented under subclass 369. Means to operate several stops in combination.

371	Celeste:
	This subclass is indented under subclass 369. Devices to produce the "celeste" effect.

372	Swells:
	This subclass is indented under subclass 351. Mute, draw-stop, or shutters operated by knee or foot lever or bellows.

[List of Patents for class 84 subclass 373]

373

Couplers:

This subclass is indented under subclass 351. Devices to cause two notes, usually an octave apart, to sound when one key is depressed.

SEE OR SEARCH THIS CLASS, SUBCLASS:

168,	235, and 340, for other couplers.

[List of Patents for class 84 subclass 374]

374

Fan tremolos:

This subclass is indented under subclass 351. Devices to produce interruptions in the flow of sound, usually of the rotating-fan type.

SEE OR SEARCH THIS CLASS, SUBCLASS:

348,	for valve tremolos.

[List of Patents for class 84 subclass 375]

375

Minor reed:

This subclass is indented under subclass 330. Includes imitation trumpets, jews’-harps, and reed-horns of variable pitch.

SEE OR SEARCH THIS CLASS, SUBCLASS:

350,	for accurate tuning means.

SEE OR SEARCH CLASS:

116,	Signals and Indicators, subclasses 137+ and 140 for ordinary fish-horns or dinner-horns.
623,	Prosthesis (i.e., Artificial Body Members) Parts Thereof or Aids and Accessories Therefor, subclass 9 for artificial larynxes.

[List of Patents for class 84 subclass 376]

376

Accordions:

This subclass is indented under subclass 375. Wind is supplied by a hand-operated bellows and the reeds are controlled by valves and keys.

(1) Note. Some forms are called "concertinas".

SEE OR SEARCH THIS CLASS, SUBCLASS:

168,	255 and 340, for other couplers.

377	Harmonicas:
	This subclass is indented under subclass 375. Mouth-blown instruments usually sounding chords and rarely having keys.

378	With resonance chambers:
	This subclass is indented under subclass 377. A resonance tube or chamber is added.

379	Supports:
	This subclass is indented under subclass 377. Devices to support a harmonica on another instrument or on the player’s body.

380	Wood winds:
	This subclass is indented under subclass 330. Includes patents for features that are readily applicable to various instruments.

381	Duplex:
	This subclass is indented under subclass 380. Instruments having two tubes to be blown and fingered simultaneously.

382	Clarinets:
	This subclass is indented under subclass 380. Includes features specially applicable to clarinets.

383	Mouthpieces:
	This subclass is indented under subclass 382. Single-reed mouthpieces and elements thereof.

384	Flutes:
	This subclass is indented under subclass 380. Features pertaining to flutes and similar instruments that give the octave on overblowing.

385	Saxophones:
	This subclass is indented under subclass 380. Details not applicable to other instruments.

386	Pitch-changing devices:
	This subclass is indented under subclass 380. Devices for changing the key or the pitch; transposers.

387	Brasses:
	This subclass is indented under subclass 330. Band instruments commonly called "brasses", whatever their specific names may be; this subclass includes combinations and features not classifiable below.

388	Valve type:
	This subclass is indented under subclass 387. Instruments, of which the cornet is typical, usually having three piston-valves.

389	With four valves:
	This subclass is indented under subclass 388. Cornets, etc., having four or more valves.

390	Rotary movement:
	This subclass is indented under subclass 388. The valves rotate.

391	Helical or sliding movement:
	This subclass is indented under subclass 388. The valves have a combined rotating and sliding movement or the engaging surfaces of the valve and its seat are planes.

392	Piston details:
	This subclass is indented under subclass 388. Details of the piston-valve.

393	With substitute tubes:
	This subclass is indented under subclass 388. Each valve controls two tubes of different length, often symmetrically placed, whereby the difference in timbre between open and valve tones is diminished.

394	Tuning devices:
	This subclass is indented under subclass 388. Means to change the key or pitch.

395	Trombones:
	This subclass is indented under subclass 387. Instruments in which the changes in length of the vibrating air column depend on a slide.

396	Tuning devices:
	This subclass is indented under subclass 395. Means to change the key or pitch specially adapted to a trombone.

397	Drainage:
	This subclass is indented under subclass 387. Water-keys and analogous devices.

398	Mouthpieces:
	This subclass is indented under subclass 387. Cornet and similar mouthpieces, usually cup-shaped.

399	Adjustable:
	This subclass is indented under subclass 398. Adjustable in length or internal shape or having interchangeable parts.

400	Mutes:
	This subclass is indented under subclass 387. Cornet-mutes to enable the player to produce a softer tone than usual.

401	Tremolos:
	This subclass is indented under subclass 387. Devices by which a tremolo effect may be produced.

[List of Patents for class 84 subclass 402]

402

Rigid vibrators:

This subclass is indented under subclass 1. Miscellaneous constructions and features.

(1) Note. This group is intended to take all solid sounding-bodies except strings. They are sometimes called "autophones" or "percussion instruments".

SEE OR SEARCH THIS CLASS, SUBCLASS:

2,	3, 170, and 171, for attachments to a piano or organ.

403	Bars and supports:
	This subclass is indented under subclass 402. Bars supported at nodal points to vibrate transversely and means for supporting them; also some end-supported bars and some resonators; hand-strikers are used.

[List of Patents for class 84 subclass 404]

404

With strikers:

This subclass is indented under subclass 403. Bars furnishing the notes of a scale and strikers therefor.

(1) Note. Called "xylophones, toy pianos, pianos, pianos without strings, chimes," etc.

SEE OR SEARCH CLASS:

116,	Signals and Indicators, appropriate subclasses for mechanically operated signals.
340,	Communications: Electrical, subclasses 384.1 -404.3 for electrically operated audible signals.

405	With electric action:
	This subclass is indented under subclass 403. The bars are vibrated by electromagnets.

[List of Patents for class 84 subclass 406]

406

Bells:

This subclass is indented under subclass 402. A musical instrument usually including a plurality of bells and strikers or equivalents.

SEE OR SEARCH CLASS:

116,	Signals and Indicators, subclass 25 for single bells.

[List of Patents for class 84 subclass 407]

407

With electric action:

This subclass is indented under subclass 406. The strikers are actuated or controlled by electromagnets.

SEE OR SEARCH CLASS:

340,	Communications: Electrical, subclasses 392.1 -396.1 for an electrically operated signal bell.

[List of Patents for class 84 subclass 408]

408

Tongues:

This subclass is indented under subclass 402. Short bars fixed at one end like the teeth of a comb and vibrated by a pick.

(1) Note. Most familiar in the Swiss music-box and indented subclasses.

SEE OR SEARCH THIS CLASS, SUBCLASS:

94.1	through 101, for combs.

[List of Patents for class 84 subclass 409]

409

Forks:

This subclass is indented under subclass 402. A musical instrument comprising tuning-forks and their strikers.

SEE OR SEARCH THIS CLASS, SUBCLASS:

457,	for single forks.

[List of Patents for class 84 subclass 410]

410

Resonators:

This subclass is indented under subclass 402. Hollow bodies serving as resonators for a bar, fork, etc.

SEE OR SEARCH CLASS:

181,	Acoustics, for pertinent subclass(es) as determined by schedule review.

411	Drums:
	This subclass is indented under subclass 1. Miscellaneous drums not classifiable in the subclasses indented hereunder.

412	Collapsible:
	This subclass is indented under subclass 411. Drums collapsible for convenience of transportation.

413	Cord tighteners:
	This subclass is indented under subclass 411. Means for tightening cords that stretch the heads.

414	Head material:
	This subclass is indented under subclass 411. Unusual materials for the head.

415	Snares:
	This subclass is indented under subclass 411. Miscellaneous features of construction.

416	Material:
	This subclass is indented under subclass 415. The invention is in the material used.

417	Inside:
	This subclass is indented under subclass 415. The snares are inside the head.

418	Tambourines:
	This subclass is indented under subclass 411. Shallow drums with a single head.

419	Tympani:
	This subclass is indented under subclass 411. Kettledrums and tuning means therefor.

420	Toy:
	This subclass is indented under subclass 411. Small cheap drums used as toys.

[List of Patents for class 84 subclass 421]

421

Supports:

This subclass is indented under subclass 420. Devices for supporting drums.

SEE OR SEARCH CLASS:

248,	Supports, subclasses 200 through 316.8,for attachments to a drum for supporting bells, cymbals, etc.

422.1	Drum and cymbal beaters:
	This subclass is indented under subclass 1. Subject matter which are foot-operated bass drum beaters.

422.2	Combined:
	This subclass is indented under subclass 422.1. Subject matter combined with cymbal beaters.

422.3	Hi-hat:
	This subclass is indented under subclass 422.1. Subject matter which are cymbal beaters (e.g., Hi-Hat, etc.).

422.4	Drumsticks:
	This subclass is indented under subclass 422.1. Subject matter which are drumsticks.

423	Keyboards:
	Miscellaneous patents involving several features or features not specifically classified.

424	Plurality of manuals:
	This subclass is indented under subclass 423. Keyboards like those of a pipe-organ and couplers therefor.

425	Auxiliary:
	This subclass is indented under subclass 423. Keys of one set operate, respectively, keys of another set.

426	Pedal:
	This subclass is indented under subclass 425. The keys of the first set are foot-operated.

427	Plurality of touch plates:
	This subclass is indented under subclass 423. All or some of the keys have two places for fingering; stepped keys.

428	Whole-tone scale:
	This subclass is indented under subclass 427. Successive keys furnish notes a whole tone apart; Janko keyboards, etc.

429	Curved front:
	This subclass is indented under subclass 423. The front ends of the keys lie along a curved line.

430	Key bottoms:
	This subclass is indented under subclass 423. Changes in the part of the case which supports the key-frame.

431	Folding:
	This subclass is indented under subclass 430. The bottom and keys fold into the case.

432	Key frames adjustable:
	This subclass is indented under subclass 423. Means to vary the striking-point in a horizontal piano or to level the key-frame.

433	Keys:
	This subclass is indented under subclass 423. The improvement can be embodied in a single key.

434	Fulcrums and guides:
	This subclass is indented under subclass 433. Improvements in both fulcrum and guide.

435	Fulcrums:
	This subclass is indented under subclass 433. Improvements in the fulcrum.

[List of Patents for class 84 subclass 436]

436

Guides:

This subclass is indented under subclass 433. Improvements in the guiding devices.

SEE OR SEARCH THIS CLASS, SUBCLASS:

438,	for manufacturing processes.

437	Plating:
	This subclass is indented under subclass 433. Improvements in the ivory or other covering.

438	Manufacturing processes:
	This subclass is indented under subclass 423. Various processes of manufacture.

[List of Patents for class 84 subclass 439]

439

Touch regulators:

This subclass is indented under subclass 423. Means to adjust the depth or other characteristics of the touch.

SEE OR SEARCH THIS CLASS, SUBCLASS:

435,	for fulcrums.
467,	for practice key boards.

440	Resistance:
	This subclass is indented under subclass 439. Means to adjust the resistance of the keys.

[List of Patents for class 84 subclass 441]

441

Key holders:

This subclass is indented under subclass 423. Means to hold down a depressed key, so as to sustain the sound, generally in organs.

SEE OR SEARCH THIS CLASS, SUBCLASS:

167,	for devices to hold all the keys.

442	Key selectors:
	Means for selecting out of the twelve keys of an octave those needed for any diatomic scale.

[List of Patents for class 84 subclass 443]

443

Chord players:

Means whereby a single key or button sounds a chord.

SEE OR SEARCH THIS CLASS, SUBCLASS:

317,	for devices to produce chords.

444	Pedal operated:
	This subclass is indented under subclass 443. Means whereby a single pedal sounds a chord.

[List of Patents for class 84 subclass 445]

445

Transposers:

Devices whereby each sound produced is systematically different in pitch from that normally associated with the key struck.

(1) Note. Includes pneumatic or electric devices.

SEE OR SEARCH THIS CLASS, SUBCLASS:

442,	for key selectors.

446	Auxiliary keyboard:
	This subclass is indented under subclass 445. A shiftable keyboard superposed on the ordinary one.

447	Keyboard shifted:
	This subclass is indented under subclass 445. The keyboard is shifted relatively to the action.

448	Intermediate parts shifted:
	This subclass is indented under subclass 445. Parts between the keyboard and sounders are shifted.

449	Sounders shifted:
	This subclass is indented under subclass 445. The sounders are shifted.

450	Solo attachments:
	Devices for emphasizing the highest or lowest note of a chord; "melody attachment".

451	Special or enharmonic scales:
	Pianos or organs furnishing more than twelve notes to the octave or tuned to give a scale different from the equally-tempered scale of the piano; special keyboards and connections therefrom; quarter-tone instruments; enharmonic instruments.

[List of Patents for class 84 subclass 452]

452

Materials:

Patents in which the novelty resides in a substitution of material.

(1) Note. See this class, subclasses 193 and 291.

[List of Patents for class 84 subclass 453]

453

ACCESSORIES:

This subclass is indented under the class definition. Devices used in connection with a musical instrument, but not necessary to the production of music.

(1) Note. Includes testing devices.

SEE OR SEARCH THIS CLASS, SUBCLASS:

169,	for indicators related to a self-playing instrument.

SEE OR SEARCH CLASS:

248,

Supports, subclasses 396 and 397 for a piano stool or bench having a tiltable support surface which may remain horizontal while the occupant is playing a piano manually, but which may be tilted forwardly to support the occupant in a position to facilitate pumping an organ bellows or player piano mechanism with his feet, and subclasses 441.1-465.1 for an easel, book, or music score holder.

[List of Patents for class 84 subclass 454]

454

Tuning devices:

This subclass is indented under subclass 453. Miscellaneous devices.

(1) Note. This subclass and the subclasses indented under it include devices temporarily used in tuning, usually not connected to the instrument to be tuned. Some of them furnish a note of standard pitch, others are merely tools.

455	Strings:
	This subclass is indented under subclass 454. Strings, usually on a graduated bar; monochord; sonometer.

456	Pipes and reeds:
	This subclass is indented under subclass 454. Pitch-pipes, reeds, etc., furnishing one or more notes of definite pitch.

[List of Patents for class 84 subclass 457]

457

Forks:

This subclass is indented under subclass 454. Tuning-forks.

SEE OR SEARCH THIS CLASS, SUBCLASS:

409,	for forks mounted to form a musical instrument.

458	Tools and machines:
	This subclass is indented under subclass 454. Machines for both shaping and blowing reeds; also some hand tools.

459	Tuning hammers:
	This subclass is indented under subclass 458. Piano-tuners’ wrenches.

460	Felt pickers:
	This subclass is indented under subclass 458. Needles and carriers for picking felt hammer-heads.

[List of Patents for class 84 subclass 461]

461

Recording devices:

This subclass is indented under subclass 453. Devices for recording the movement of keys of a keyboard.

SEE OR SEARCH CLASS:

234,	Selective Cutting (e.g., Punching), subclasses 49-50 , if the record is made by selectively perforating a moving sheet; subclasses 109-119 and 123-125 for a keyboard controlled selective cutting device in general.

462	Electric:
	This subclass is indented under subclass 461. These devices involve electric circuits.

463	Applying expression lines:
	This subclass is indented under subclass 461. Means for applying expression lines or marks to a record-sheet.

[List of Patents for class 84 subclass 464]

464

Producing color or light effects:

This subclass is indented under subclass 453. Devices for producing light or color effects combined with an instrument for producing music.

SEE OR SEARCH CLASS:

239,	Fluid Sprinkling, Spraying, and Diffusing, subclass 18 for ornamental fountains having means to light or illuminate the fountain.
315,	Electric Lamp and Discharge Devices: Systems, pertinent subclasses as determined by schedule review, for electric systems for supplying electric energy to electric lamps.
446,	Amusement Devices: Toys, subclass 200 for a figure toy which moves in time with a musical instrument; and subclasses 202-209 for other mouthpiece-actuated toys.

[List of Patents for class 84 subclass 465]

465

Exercising devices:

Devices to aid students in learning to play an instrument.

SEE OR SEARCH THIS CLASS, SUBCLASS:

281,	for positioning devices.

466	For singers:
	This subclass is indented under subclass 465. Devices to aid in voice-training.

[List of Patents for class 84 subclass 467]

467

For pianists:

This subclass is indented under subclass 465. Includes practice-keyboards; "claviers".

SEE OR SEARCH THIS CLASS, SUBCLASS:

440,	for key resistance devices.

SEE OR SEARCH CLASS:

434,	Education and Demonstration, subclasses 176 , 202, and 227-233 for other teaching devices having key-boards.
482,	Exercise Devices, particularly subclasses 44 -50 for hand, wrist, or finger exercise apparatus in general.
601,	Surgery: Kinesitherapy, subclass 40 for hand and finger exercise devices.

468	Attached to performer:
	This subclass is indented under subclass 467. Devices attached to the player’s hand or body.

[List of Patents for class 84 subclass 469]

469

Armrest rail:

This subclass is indented under subclass 467. A rail fixed to the piano-case to position the player’s arm.

SEE OR SEARCH THIS CLASS, SUBCLASS:

328,	for arm, hand, or finger rests.

[List of Patents for class 84 subclass 470]

470

Teaching devices:

This subclass is indented under subclass 453. Devices for use in teaching music, some with sounders; charts; indicators.

SEE OR SEARCH CLASS:

434,	Education and Demonstration, for pertinent subclasses as determined by schedule review for other teaching devices.

471	Charts or boards:
	This subclass is indented under subclass 470. Various kinds of charts.

[List of Patents for class 84 subclass 472]

472

Easel type:

This subclass is indented under subclass 471. Devices adapted to stand vertically and others of analogous construction and use.

SEE OR SEARCH THIS CLASS, SUBCLASS:

477,	for devices in which a note, etc., is caused to appear on the staff upon pressing a key.

473	With transposing slide:
	This subclass is indented under subclass 471. Devices having a slide for illustrating change of key.

474	With transposing dial:
	This subclass is indented under subclass 471. Similar devices having a dial.

475	For transcribing:
	This subclass is indented under subclass 471. Various devices useful in writing music, such as from a record or for a transposing instrument.

[List of Patents for class 84 subclass 476]

476

Blocks:

This subclass is indented under subclass 470. Blocks or cards having musical characters.

SEE OR SEARCH CLASS:

273,	Amusement Devices: Games, subclasses 292 -308 for card or tile games which may have an educational benefit, and see especially subclass 301 thereof for musical indicia.
434,	Education and Demonstration, subclasses 208 and 403 for other educational blocks or cards.
446,	Amusement Devices: Toys, subclasses 85 -128 for toy blocks; and subclass 147 for toy cards.

477	Indicators:
	This subclass is indented under subclass 470. Miscellaneous visual devices responding to movements of keys or directing their movement or showing note relationships.

478	For keyboard:
	This subclass is indented under subclass 477. To be used on a keyboard.

479	Single position:
	This subclass is indented under subclass 478. A card or board bearing indicia to register with the keys of the instrument-keyboard.

480	With transposing slide:
	This subclass is indented under subclass 479. The card has a slide to indicate various major or minor keys.

481	Plurality of cards:
	This subclass is indented under subclass 479. A plurality of cards, each for a single key.

482	Shiftable:
	This subclass is indented under subclass 478. The card is shifted along the keyboard for transposition.

483.1	Tune sheets:
	This subclass is indented under subclass 477. Subject matter having sheets bearing the music and located with special reference to the keys or sounders.

483.2	Notation systems:
	This subclass is indented under subclass 483.1. Subject matter including notation systems.

484	For tempo:
	This subclass is indented under subclass 477. Devices for indicating the tempo or rhythm.

485	For fingering:
	This subclass is indented under subclass 477. The music-sheet has marks showing what finger is to be used in producing a note.

[List of Patents for class 84 subclass 486]

486

Leaf turners:

This subclass is indented under subclass 453. Patents showing constructions not clearly belonging in one of the following subclasses or showing features applicable to various types of leaf-turners.

(1) Note. Leaf-turners are devices to be attached to a music-stand or to the music-desk of a piano to enable a player to turn one or more leaves of music from right to left. In some cases the player releases a source of power, in others he furnishes the power. In either case he may use his hand, knee, or foot, and the terms "releaser" and "finger-piece" are used generically herein to include also knee-levers and foot-levers. Often a pedal is connected to operate a finger-key. Usually each leaf is attached by clips to one or two arms extending from a solid or tubular shaft pivoted near the line of fold of the music-sheets or the line of the back of a bound book, said arms extending along the top or bottom edge of the leaf or along both. This classification is based, first, on the immediate source of the power that turns the leaf-motor, gravity, spring, or hand--and, second, on whether there is a plurality of parts or a single one of each kind. The parts considered are only those of turning a leaf from right to left. In many instances there are keys or pedals to return the leaves from left to right. These are disregarded in the classification.

(2) Note. Patents for some features of construction that are not suggested by these titles are cross-referenced into this subclass.

SEE OR SEARCH CLASS:

40,	Card, Picture, or Sign Exhibiting, subclasses 524 -528, 529 for means to feed a continuous sheet of music and 530-537 for means to turn the leaves of a book.
248,	Supports, subclasses 441.1 -465.1 for an easel, book, or music score holder.

[List of Patents for class 84 subclass 487]

487

Motor operated:

This subclass is indented under subclass 486. In these generally a spring-motor is released repeatedly to turn leaf-holding arms forward and back; the motor must be rewound from time to time.

(1) Note. Some patents show an electric motor.

488	Gravity operated:
	This subclass is indented under subclass 486. The leaves are moved by the weight of some part.

[List of Patents for class 84 subclass 489]

489

Hand and spring operated arms:

This subclass is indented under subclass 486. The arms are started by hand and their movement continued by springs.

(1) Note. Each arm has a spring tending to carry it from right to left. The arm is held by a latch, catch, detent, or dog. This may be liberated by a releaser, trigger, key, or finger-piece.

490	Plurality of latches:
	There is a latch for each arm.

491	Fixed latches:
	This subclass is indented under subclass 490. The latches are fixed and the arms are moved slightly to release them.

492	Plurality of releasers:
	This subclass is indented under subclass 490. There is a releaser, key, or pedal for each arm.

493	Latches and releasers pivoted:
	This subclass is indented under subclass 492. Both latches and releasers are pivoted.

494	Integral:
	This subclass is indented under subclass 493. Each latch is integral with its releaser and is pivoted.

495	Single latch:
	One latch holds all the arms, so only one releaser is needed.

496	Fixed latch:
	This subclass is indented under subclass 495. The latch is fixed and commonly it holds directly the outermost arm.

497	Sliding latch:
	This subclass is indented under subclass 495. The latch slides to release the arms successively.

498	Escapement:
	This subclass is indented under subclass 495. The latch has means to catch the following arm before or as it releases the front one.

499	Air operated:
	This subclass is indented under subclass 498. The latch is operated by a puff of air.

[List of Patents for class 84 subclass 500]

500

Single spring arm:

This subclass is indented under subclass 486. There is only one arm, and this is spring-operated.

SEE OR SEARCH THIS CLASS, SUBCLASS:

516,	for single arm devices.
517,	for single transfer bar devices.

501	Latch and releaser integral:
	This subclass is indented under subclass 500. The two functions are served by one integral piece.

502	Player-operated arms:
	This subclass is indented under subclass 486. The player supplies the power to turn the arms through finger-pieces and connections called "actuators".

503	Plurality of actuators:
	This subclass is indented under subclass 502. One for each arm.

504	Plurality of finger pieces:
	This subclass is indented under subclass 503. One for each arm.

505	Actuators pivoted:
	This subclass is indented under subclass 504. The actuator is pivoted; often it is a gear or segmental gear.

506	Actuators and finger pieces integral:
	This subclass is indented under subclass 504. Each finger-piece is integral with its actuator. The latter is often toothed.

507	Single finger piece:
	This subclass is indented under subclass 503. One finger-piece operates successively all the actuators and arms; single actuator operates all the arms.

508	Progressive action:
	The actuator moves on step by step to shift the successive arms.

509	Arms and actuator on different axes:
	This subclass is indented under subclass 508. The arms and actuator are pivoted on different axes.

510	With segmental gear:
	This subclass is indented under subclass 509. The actuator has a segmental gear.

511	Sliding actuator:
	The actuator slides.

512	With segmental rack:
	This subclass is indented under subclass 511. It includes a segmental rack.

513	Repeating action:
	The actuator after shifting one arm returns for the next one.

514	Arms and actuator on different axes:
	This subclass is indented under subclass 513. The arms and actuator are pivoted on different axes.

515	Sliding actuator:
	This subclass is indented under subclass 513. The actuator slides.

516	Single arm:
	This subclass is indented under subclass 486. Devices for turning a single leaf or sometimes a sheet around its center.

517	Single transfer bar:
	This subclass is indented under subclass 486. There are no arms with clips, but a single actuator engages successively leaves or attachments on them.

518	With buckling devices:
	This subclass is indented under subclass 517. Devices for partly raising a leaf, so that the bar or finger may pass under it.

519	With suction devices:
	This subclass is indented under subclass 517. The leaf is lifted by a suction-head.

520	Leaves prepared:
	This subclass is indented under subclass 517. The leaves are notched or otherwise modified to cooperate with the mechanism.

521	With magnetic disks:
	This subclass is indented under subclass 520. The leaves carry iron disks to be attracted by magnets on the transfer-bar.

[List of Patents for class 84 subclass 600]

600

Electrical musical tone generation:

This subclass is indented under subclass 1. Subject matter including means for generating or modifying electric currents or potentials to produce varying electric currents or potentials in combination with, or intended for converting the varying electric currents or potentials into sound vibrations for the production of musical tones.

(1) Note. For devices which generate or modify an electric current or potential so as to produce a particular waveform, see the search notes below.

SEE OR SEARCH CLASS:

307,	Electrical Transmission or Interconnection Systems, subclasses 106 -108 for waveform or waveshape determinative circuits.
310,	Electrical Generator or Motor Structure, appropriate subclasses for electrical generators, particularly subclass 111 for generated wave modifications; subclass 160 for rotary frequency converters, and subclasses 166-172 for induction and variable reluctance type A. C. generators.
322,	Electricity: Single Generator Systems, appropriate subclasses for miscellaneous generator systems for generating electric currents and potentials.
327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses for miscellaneous nonlinear circuits using active devices such as tubes or transistors.
331,	Oscillators, appropriate subclasses for electrical oscillator systems, per se.
333,	Wave Transmission Lines and Networks, subclass 20 for electric waveshaping networks of the passive type and subclass 167 for electric wave filters.
336,	Inductor Devices, appropriate subclasses for inductive reactors and transformers which are provided with fixed or movable elements (e.g., having a moving armature to modify the impedance of an inductive reactor).
338,	Electrical Resistors, subclass 69 for mechanically variable resistors actuated by musical instrument playing keys.
363,	Electric Power Conversion Systems, appropriate subclasses for electric power conversion systems; particularly subclasses 13 -147 for rectifying and inverting systems, and subclasses 157-177 for frequency conversion systems.
704,	Data Processing: Speech Signal Processing, Linguistics, Language Translation, and Audio Compression/Decompression, subclasses 258 -269 for speech synthesis.

[List of Patents for class 84 subclass 601]

601

Data storage:

This subclass is indented under subclass 600. Subject matter wherein tone characteristic informations such as timbre, envelope, harmonic contents, pitch or etc., are retained and retrievable to produce musical tone.

SEE OR SEARCH CLASS:

324,	Electricity: Measuring and Testing, subclasses 111 and 113 for storing or recording voltage or current.
360,	Dynamic Magnetic Information Storage and Retrieval, subclass 32 for prior analog to digital conversion; subclasses 55-68 for magnetic recording and producing; subclass 131 for recording medium, per se.
365,	Static Information Storage and Retrieval, appropriate subclasses for memory, per se, and subclass 48 for magnetic analog storage.
369,	Dynamic Information Storage and Retrieval, subclass 63 for sound reproduction for toy or novelty; subclass 86 for acoustic signal storage and retrieval; subclasses 272.1-291.1 for storage medium, per se.
704,	Data Processing: Speech Signal Processing, Linguistics, Language Translation, and Audio Compression/Decompression, subclasses 206 -210 for storage of pitch and formats.
720,	Dynamic Optical Information Storage or Retrieval, subclasses 718 through 746for optical storage medium structure.

[List of Patents for class 84 subclass 602]

602

Digital memory circuit (e.g., RAM, ROM, etc.):

This subclass is indented under subclass 601. Subject matter wherein the tone characteristic information is stored by digital memory circuit in a discrete format (e.g., RAM, ROM, etc.) to produce musical tone.

(1) Note. This subclass does not provide for generating musical tone based on digital combinational circuit (see this class subclass 647 for digital combinational circuit).

SEE OR SEARCH CLASS:

360,	Dynamic Magnetic Information Storage and Retrieval, subclass 32 for prior analog to digital conversion before storage; subclass 39 for digital storage; subclasses 55-68 for magnetic recording and retrieval; subclasses 131-136 for storage medium, per se.
365,	Static Information Storage and Retrieval, appropriate subclasses for specific memory systems, per se.
711,	Electrical Computers and Digital Processing Systems: Memory, subclasses 100 -173 for generic storage accessing and control in digital data processing systems.

[List of Patents for class 84 subclass 603]

603

Sampling (e.g., with A/D conversion):

This subclass is indented under subclass 602. Subject matter wherein an analog sound is digitized and stored for future retrieval.

SEE OR SEARCH CLASS:

341,	Coded Data Generation and Conversion, subclasses 122 -125 for generic A/D conversion with sampling.
360,	Dynamic Magnetic Information Storage or Retrieval, subclass 32 for analog to digital conversion prior to storage.
700,	Data Processing: Generic Control Systems or Specific Applications, subclass 73 for sampled data control systems, per se.

604	Waveform memory:
	This subclass is indented under subclass 602. Subject matter wherein a waveform is digitally stored.

[List of Patents for class 84 subclass 605]

605

Read out at different rates:

This subclass is indented under subclass 604. Subject matter wherein the waveforms are read out from memory at various rates that correspond to desired pitches.

SEE OR SEARCH CLASS:

365,	Static Information and Retrieval, subclass 230 .01 for addressing a waveform memory, per se.

[List of Patents for class 84 subclass 606]

606

Read out at fixed rate:

This subclass is indented under subclass 604. Subject matter wherein the waveforms are read out from memory at a constant rate.

SEE OR SEARCH THIS CLASS, SUBCLASS:

605,	for read out at different rates.

[List of Patents for class 84 subclass 607]

607

Recursive algorithm:

This subclass is indented under subclass 604. Subject matter wherein a plural period waveform is achieved by rereading the same waveform from the same memory location.

SEE OR SEARCH THIS CLASS, SUBCLASS:

605,	for read out at different rates.

SEE OR SEARCH CLASS:

700,	Data Processing: Generic Control Systems or Specific Applications, subclass 89 for data processing control system with specific algorithm

[List of Patents for class 84 subclass 608]

608

Fourier coefficient memory:

This subclass is indented under subclass 602. Subject matter wherein storage locations are provided for the Fourier coefficients.

SEE OR SEARCH THIS CLASS, SUBCLASS:

602,	for digital memory circuit.

SEE OR SEARCH CLASS:

708,	Electrical Computers: Arithmetic Processing and Calculating, subclasses 403 -409 and 821 for digital and analog Fourier transforms.

[List of Patents for class 84 subclass 609]

609

Note sequence:

This subclass is indented under subclass 602. Subject matter wherein a succession of musical notes is sequentially processed by digital memory circuit for performance or comparison.

SEE OR SEARCH CLASS:

446,	Amusement Devices: Toys, subclass 408 for simulated musical instruments.

610	Accompaniment:
	This subclass is indented under subclass 609. Subject matter wherein the stored sequence is used as a musical support for a voice or melody.

611	Rhythm:
	This subclass is indented under subclass 610. Subject matter wherein the information represents the timing intervals of the musical piece.

612	Tempo control:
	This subclass is indented under subclass 611. Subject matter wherein the rate or speed of rhythm is variable.

613	Chords:
	This subclass is indented under subclass 610. Subject matter wherein the note sequence contains a plurality of notes played simultaneously.

614	Reiteration:
	This subclass is indented under subclass 610. Subject matter wherein the plural tones are repetitively played in sequence.

615	Selecting circuits:
	This subclass is indented under subclass 602. Subject matter comprising a circuit which selects any musical parameter, e.g., pitch, timbre, etc.

616	Fundamental tone detection or extraction:
	This subclass is indented under subclass 615. Subject matter wherein the fundamental or pitch is detected and used to activate or modify a musical system.

[List of Patents for class 84 subclass 617]

617

Multiplexing or scanning:

This subclass is indented under subclass 615. Subject matter wherein the selecting circuits are assigned by time division multiplexing or scanning.

SEE OR SEARCH CLASS:

340,	Communications: Electrical, subclasses 4.37 and 4.4-4.42 for selective scanning devices in audio reproducing.
370,	Multiplex Communications, appropriate subclasses for time division multiplexing, per se.

[List of Patents for class 84 subclass 618]

618

Priority or preference circuits:

This subclass is indented under subclass 615. Subject matter wherein a plurality of musical notes or keys are selected with a certain note or notes having precedence over others selected e.g., highest or lowest notes having priority over any other selected, etc.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 1 -99 for signal discriminating, comparing, or selecting.

[List of Patents for class 84 subclass 619]

619

Transposition:

This subclass is indented under subclass 615. Subject matter wherein a musical piece is written or performed in a key other than the original or given key.

SEE OR SEARCH CLASS:

363,	Electric Power Conversion Systems, subclasses 157-177 for converting a first frequency into a second frequency.

620	Stops:
	This subclass is indented under subclass 615. Subject matter wherein a circuit or system selects a musical voice, tone color, timbre or electrically simulated organ pipe sound.

[List of Patents for class 84 subclass 621]

621

Noise reduction (e.g., error prevention, etc.):

This subclass is indented under subclass 602. Subject matter wherein circuitry is provided to reduce electrical noises, transients or unwanted disturbances.

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclasses 71.1-71.14 for acoustical noise or sound cancellation; subclasses 94.1-94.9 for noise or distortion suppression.
702,	Data Processing: Measuring, Calibrating, or Testing, subclasses 191 -195 for noise removal or suppression in a measured signal of a data processing measuring system

[List of Patents for class 84 subclass 622]

622

Tone synthesis or timbre control:

This subclass is indented under subclass 602. Subject matter wherein the harmonic content of a note is controlled or modified.

SEE OR SEARCH CLASS:

307,	Electrical Transmission or Interconnection Systems, subclasses 106 -108 for waveform or waveshape determinative systems.
327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 100 -333 for miscellaneous converting, shaping, or generating.
333,	Wave Transmission Lines and Networks, subclass 28 for audio tone controls; subclasses 167-185 for lumped parameter filters, per se.
381,	Electrical Audio Signal Processing Systems and Devices, subclasses 101 through 103for automatic tone control or equalization of an audio signal; subclass 118 for signal processing of musical instruments, per se.
708,	Electrical Computers: Arithmetic Processing and Calculating, subclasses 300 -323 for digital filtering by a calculating computer.

[List of Patents for class 84 subclass 623]

623

Time varying or dynamic Fourier components:

This subclass is indented under subclass 622. Subject matter wherein the Fourier components are time varying or dynamic.

SEE OR SEARCH THIS CLASS, SUBCLASS:

608,	for a constant stored Fourier component.

[List of Patents for class 84 subclass 624]

624

Modulation:

This subclass is indented under subclass 622. Subject matter wherein tones are synthesized or modified by varying a carrier wave in accordance with a modulation wave.

SEE OR SEARCH CLASS:

332,	Modulators, subclasses 117-143 for phase or frequency modulation; subclasses 149-182 for amplitude modulation.
360,	Dynamic Magnetic Information Storage or Retrieval, subclasses 29 through 30for the frequency modulation of stored data.

[List of Patents for class 84 subclass 625]

625

Mixing:

This subclass is indented under subclass 622. Subject matter wherein two or more signals are combined to form a composite waveform.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 113 -123 for a miscellaneous frequency mixing circuit.
369,	Dynamic Information Storage or Retrieval, subclass 4 for mixing signals that originate from storage.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 119 for audio system mixers, per se.

[List of Patents for class 84 subclass 626]

626

Expression or special effects (e.g., force or velocity responsive, etc.):

This subclass is indented under subclass 602. Subject matter for providing an indication of feeling or artistic execution to the musical tones.

SEE OR SEARCH CLASS:

73,	Measuring and Testing, subclasses 488 -551 for velocity measuring, per se.
327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 261 -290 for miscellaneous delay circuits.
356,	Optics: Measuring and Testing, subclass 28 for measuring key switch velocity optically.
361,	Electricity: Electrical Systems and Devices, subclasses 283.1 -283.4 for pressure (force) responsive capacitors.

[List of Patents for class 84 subclass 627]

627

Envelope shaping (i.e., attack, decay, sustain or release):

This subclass is indented under subclass 626. Subject matter for providing or modifying an amplitude contour of an activated tone.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 306 -333 for signal shaping by amplitude control.
333,	Wave Transmission Lines and Networks, appropriate subclasses for networks delay.

628	Portamento or glissando:
	This subclass is indented under subclass 626. Subject matter for producing an audible continuous glide from one tone to a second tone.

[List of Patents for class 84 subclass 629]

629

Vibrato or tremolo:

This subclass is indented under subclass 626. Subject matter wherein an audio tone is frequency or amplitude modulated with a subaudio frequency.

SEE OR SEARCH CLASS:

331,	Oscillators, subclass 178 for producing vibrato in the oscillator output frequency.
332,	Modulators, subclasses 117-143 for frequency modulation which produces vibrato; subclasses 149-182 for amplitude modulation which produces tremolo.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 62 for tremolo or vibrato effects.

[List of Patents for class 84 subclass 630]

630

Reverberation:

This subclass is indented under subclass 626. Subject matter for providing time delays that simulate a plurality of acoustic reflections of a given tone; e.g., echo, etc.

SEE OR SEARCH CLASS:

367,	Communications, Electrical: Acoustic Wave Systems and Devices, subclasses 87 -116 for echo systems, per se.
381,	Electrical Audio Signal Processing Systems and Devices, subclasses 63-65 for reverberation.

[List of Patents for class 84 subclass 631]

631

Chorus, ensemble, or celeste:

This subclass is indented under subclass 626. Subject matter providing for the combining of a slightly detuned tone with the original tone.

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclasses 89 through 336for rotating speakers that produce a chorus or "Leslie" effect.

632	Chiff or percussive transients:
	This subclass is indented under subclass 626. Subject matter wherein transients are introduced into the initial sounding portion of the envelope to simulate the hiss or noise of an organ pipe.

[List of Patents for class 84 subclass 633]

633

Loudness control:

This subclass is indented under subclass 626. Subject matter wherein the amplitude or volume of the musical tones may be regulated.

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclasses 104-109 for amplitude or volume control of an audio signal.

634	Accompaniment:
	This subclass is indented under subclass 602. Subject matter wherein digital data represents a musical support or background.

635	Rhythm:
	This subclass is indented under subclass 634. Subject matter wherein the information represents timing intervals of a musical piece.

636	Tempo control:
	This subclass is indented under subclass 635. Subject matter wherein the rate or speed of rhythm is variable.

637	Chords:
	This subclass is indented under subclass 634. Subject matter wherein the data represents a plurality of musical tones to be played simultaneously.

638	Arpeggio:
	This subclass is indented under subclass 634. Subject matter wherein the data represents chord tones to be played in sequence one at a time.

[List of Patents for class 84 subclass 639]

639

Photoelectric:

This subclass is indented under subclass 601. Subject matter including optical and electrical means for storing data representative of the musical tones.

SEE OR SEARCH CLASS:

250,	Radiant Energy, subclasses 200 -239 for photocell systems.
361,	Electricity: Electrical Systems and Devices, subclasses 173 -177 for the activation of solenoids from a condition responsive photosensor.
362,	Illumination, subclass 295 for a switch which acts in response to a light source or modifier which ultimately controls, for example, an oscillator; subclass 802 for light activated switches, per se.
365,	Static Information Storage and Retrieval, subclass 112 for generic photoelectric memory systems.

[List of Patents for class 84 subclass 640]

640

Variable speed:

This subclass is indented under subclass 639. Subject matter wherein different pitches are obtained by varying the rotational speed of a diffraction or grating disk.

SEE OR SEARCH CLASS:

250,	Radiant Energy, subclass 237 for pre-photocell grating systems.
359,	Optical: Systems and Elements, subclasses 558 -576 for optical diffraction devices.

[List of Patents for class 84 subclass 641]

641

Magnetic:

This subclass is indented under subclass 601. Subject matter including magnetic and electrical means for storing data representative of the musical tones.

SEE OR SEARCH CLASS:

360,	Dynamic Magnetic Information Storage or Retrieval, subclasses 55 -68 for general features pertaining to magnetic storage of information; subclasses 131-136 for the storage medium, per se.
365,	Static Information Storage and Retrieval, subclass 48 for analog storage on magnetic medium.

642	Tape:
	This subclass is indented under subclass 641. Subject matter wherein the magnetic storage medium is in a tape form.

[List of Patents for class 84 subclass 643]

643

Capacitive:

This subclass is indented under subclass 601. Subject matter including capacitive means for storing data representative of the musical tones.

SEE OR SEARCH CLASS:

361,	Electricity: Electrical Systems and Devices, subclasses 271 -330 for capacitors, per se.
365,	Static Information Storage and Retrieval, subclass 102 for capacitative type read only memories.

644	Constructional details:
	This subclass is indented under subclass 601. Subject matter including mechanical features of the musical instrument.

[List of Patents for class 84 subclass 645]

645

MIDI (musical instrument digital interface):

This subclass is indented under subclass 601. Subject matter including an interface between an instrument and a digital processing system.

SEE OR SEARCH CLASS:

700,	Data Processing: Generic Control Systems or Specific Applications, subclasses 83 through 85for generic data processing with operator control interface.

646	Fret control:
	This subclass is indented under subclass 600. Subject matter wherein the stored data is controlled via a stringed musical instrument fingerboard, e.g., switches on a guitar fingerboard, etc.

[List of Patents for class 84 subclass 647]

647

Digital combinational circuit:

This subclass is indented under subclass 600. Subject matter wherein binary inputs are provided to digital combinational circuit to produce musical tone.

(1) Note. Digital combinational circuit performs some unique logic function such as decording, encording, multiplexing, comparison or an arithmetic operation with binary numbers.

(2) Note. This subclass does not provide for stored tone characteristic information to produce musical tone (See this class, subclass 602 for digital memory circuit).

SEE OR SEARCH CLASS:

331,	Oscillators, appropriate subclasses for oscillators used to provided a digital signal.

[List of Patents for class 84 subclass 648]

648

With frequency multiplication or division:

This subclass is indented under subclass 647. Subject matter wherein the discrete notes of a complete musical scale are obtained by varying the oscillator output frequency.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 113 -123 for miscellaneous frequency multiplication or division.
331,	Oscillators, appropriate subclasses for oscillators used to provide a digital signal.
363,	Electric Power Conversion Systems, subclass 157 for converting frequencies.
377,	Electrical Pulse Counters, Pulse Dividers, or Shift Registers: Circuits and Systems, subclasses 118 -128 for pulse frequency dividing chains; subclass 47 for pulse multiplication or division.

[List of Patents for class 84 subclass 649]

649

Note sequence:

This subclass is indented under subclass 647. Subject matter wherein a succession of musical notes is sequentially processed by digital combinational circuit for performance or comparison.

SEE OR SEARCH THIS CLASS, SUBCLASS:

609	through 614, for note sequence with digital data storage.

SEE OR SEARCH CLASS:

377,	Electrical Pulse Counters, Pulse Dividers, or Shift Registers: Circuits and Systems, subclass 26 for applications of pulse dividers utilizing memory.

650	Accompaniment (e.g., chords, etc.):
	This subclass is indented under subclass 649. Subject matter wherein the stored sequence is used as a musical support for a voice or melody.

651	Rhythm:
	This subclass is indented under subclass 650. Subject matter wherein the information represents timing intervals of the musical piece.

652	Tempo control:
	This subclass is indented under subclass 651. Subject matter wherein the rate or speed of rhythm is variable.

[List of Patents for class 84 subclass 653]

653

Selecting circuits:

This subclass is indented under subclass 647. Subject matter comprising a circuit which selects musical parameter, e.g., pitch, timbre, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

615	through 620, for selective circuit with digital storage.

SEE OR SEARCH CLASS:

200,	Electricity: Circuit Makers and Breakers, appropriate subclasses for selecting circuits in conjunction with musical instruments.
307,	Electrical Transmission or Interconnection Systems, subclasses 112 -144 for switching systems.

[List of Patents for class 84 subclass 654]

654

Fundamental tone detection or extraction:

This subclass is indented under subclass 653. Subject matter wherein the fundamental or pitch is detected and used to activate or modify a musical system.

SEE OR SEARCH THIS CLASS, SUBCLASS:

616,	for fundamental tone detection or extraction with digital storage.

[List of Patents for class 84 subclass 655]

655

Multiplexing or scanning:

This subclass is indented under subclass 653. Subject matter wherein the selecting circuits are assigned by time division multiplexing or scanning.

SEE OR SEARCH THIS CLASS, SUBCLASS:

617,	for multiplexing or scanning with digital storage.

[List of Patents for class 84 subclass 656]

656

Priority or preference circuits:

This subclass is indented under subclass 653. Subject matter wherein a plurality of musical notes or keys are selected with a certain note or notes having precedence over others, e.g., highest or lowest notes having priority, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

618,	for priority or preference circuits with digital storage.

[List of Patents for class 84 subclass 657]

657

Transposition:

This subclass is indented under subclass 653. Subject matter wherein a musical piece is written or performed in a key other than the original or given key.

SEE OR SEARCH THIS CLASS, SUBCLASS:

445,	for transposition structure.
619,	for transposition with digital storage.

[List of Patents for class 84 subclass 658]

658

Force or velocity responsive:

This subclass is indented under subclass 653. Subject matter wherein the selecting circuit is responsive to the applied pressure force or velocity.

SEE OR SEARCH THIS CLASS, SUBCLASS:

626	through 633, for force or velocity responsive with digital storage.

[List of Patents for class 84 subclass 659]

659

Tone synthesis or timbre control:

This subclass is indented under subclass 647. Subject matter wherein harmonic content of a note is controlled or modified.

SEE OR SEARCH THIS CLASS, SUBCLASS:

622	through 625, for tone synthesis or timbre control with digital storage.

[List of Patents for class 84 subclass 660]

660

Mixing:

This subclass is indented under subclass 659. Subject matter wherein two or more signals are combined to form a composite waveform.

SEE OR SEARCH THIS CLASS, SUBCLASS:

625,	for mixing with digital storage.

[List of Patents for class 84 subclass 661]

661

Filtering:

This subclass is indented under subclass 659. Subject matter wherein a desired waveform is obtained by removing one or more partials or harmonics.

SEE OR SEARCH CLASS:

307,	Electrical Transmission or Interconnection Systems, subclass 105 for harmonic filter or neutralizer.
333,	Wave Transmission Lines and Networks, subclass 186 for electromechanical filters using lumped parameters.
708,	Electrical Computers: Arithmetic Processing and Calculating, subclasses 300 -323 for digital filtering by a calculating computer.

[List of Patents for class 84 subclass 662]

662

Expression or special effects:

This subclass is indented under subclass 647. Subject matter for providing an indication of feeling or artistic execution to the musical tones.

SEE OR SEARCH THIS CLASS, SUBCLASS:

626,	for expression or special effects with digital storage.

SEE OR SEARCH CLASS:

331,	Oscillators, subclass 182 for specific amplitude control to produce tremolo.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 62 for vibrato or tremolo.

[List of Patents for class 84 subclass 663]

663

Envelope shaping (i.e., attack, decay, sustain or release):

This subclass is indented under subclass 662. Subject matter for providing or modifying an amplitude contour of an activated tone.

SEE OR SEARCH THIS CLASS, SUBCLASS:

627,	for envelope shaping with digital storage.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 306 -333 for signal shaping by amplitude control.
333,	Wave Transmission Lines and Networks, appropriate subclasses for network delay.

[List of Patents for class 84 subclass 664]

664

Chorus, ensemble, or celeste:

This subclass is indented under subclass 662. Subject matter providing for the combining of a slightly detuned tone with the original tone.

SEE OR SEARCH THIS CLASS, SUBCLASS:

631,	for chorus, ensemble, or celeste with digital storage.

[List of Patents for class 84 subclass 665]

665

Loudness control:

This subclass is indented under subclass 662. Subject matter wherein the amplitude or volume of the musical tones may be regulated.

SEE OR SEARCH THIS CLASS, SUBCLASS:

633,	for loudness control with digital storage.

[List of Patents for class 84 subclass 666]

666

Accompaniment:

This subclass is indented under subclass 647. Subject matter wherein digital data represents a musical support or background.

SEE OR SEARCH THIS CLASS, SUBCLASS:

610	through 614, for accompaniment with note sequence.
634	through 638, for accompaniment with digital memory circuit.
650	through 652, for accompaniment with note sequence of digital combinational circuit.

[List of Patents for class 84 subclass 667]

667

Rhythm:

This subclass is indented under subclass 666. Subject matter wherein the information represents timing intervals of a musical piece.

SEE OR SEARCH THIS CLASS, SUBCLASS:

611	through 612, for rhythm with note sequence of digital storage.
635	through 636, for rhythm with accompaniment of digital storage.
651	through 652, for rhythm with accompaniment of digital combinational circuit.

[List of Patents for class 84 subclass 668]

668

Tempo control:

This subclass is indented under subclass 667. Subject matter wherein the rate or speed of rhythm is variable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

612,	for tempo control with note sequence of digital storage.
636,	for tempo control with accompaniment of digital storage.
652,	for tempo control of digital combinational circuit.

[List of Patents for class 84 subclass 669]

669

Chords:

This subclass is indented under subclass 666. Subject matter wherein the data represents a plurality of musical tones to be played simultaneously.

SEE OR SEARCH THIS CLASS, SUBCLASS:

613,	for chords with digital memory circuit.
637,	for chords with accompaniment.

[List of Patents for class 84 subclass 670]

670

Constructional details:

This subclass is indented under subclass 647. Subject matter including mechanical features of the musical instrument.

SEE OR SEARCH THIS CLASS, SUBCLASS:

644,	for construction details with digital storage.

[List of Patents for class 84 subclass 671]

671

Electric analog oscillators:

This subclass is indented under subclass 600. Subject matter wherein the varying electric currents or potentials originate from an analog oscillator.

SEE OR SEARCH CLASS:

331,	Oscillators, appropriate subclasses for oscillator circuits, per se.

672	Variable frequency:
	This subclass is indented under subclass 671. Subject matter wherein the oscillator is changed so that the discrete notes of a complete musical scale are obtained.

673	With variable filtering:
	This subclass is indented under subclass 672. Subject matter wherein the output of the oscillator is applied to a filter wherein partials or harmonics to be removed can be varied.

674	With space discharging means:
	This subclass is indented under subclass 672. Subject matter wherein the oscillator includes one or more devices in which conduction of electrons takes place through a vacuum or gaseous medium.

[List of Patents for class 84 subclass 675]

675

With frequency multiplication or division:

This subclass is indented under subclass 671. Subject matter wherein the discrete notes of a musical scale are derived through frequency multipliers or dividers.

SEE OR SEARCH THIS CLASS, SUBCLASS:

648,	for frequency multiplication or division with digital combinational circuit.

[List of Patents for class 84 subclass 676]

676

With transistor:

This subclass is indented under subclass 675. Subject matter wherein the oscillator, frequency multipliers or frequency dividers include a semiconductor device with three or more electrodes.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 113 -123 for frequency conversion or control.

[List of Patents for class 84 subclass 677]

677

With space discharging means:

This subclass is indented under subclass 675. Subject matter wherein the oscillators, frequency multipliers or frequency dividers include one or more devices in which conduction of electrons takes place through a vacuum or gaseous medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:

674,	for space discharging mean with variable frequency.

[List of Patents for class 84 subclass 678]

678

Selecting circuits:

This subclass is indented under subclass 671. Subject matter including a circuit which selects a musical parameter, e.g., pitch or timbre, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

615,	for selecting circuit with digital storage.
653,	for selecting circuits with digital combinational circuit.

[List of Patents for class 84 subclass 679]

679

With transistor:

This subclass is indented under subclass 678. Subject matter wherein the oscillator, frequency multipliers or frequency dividers include a semiconductor device with three or more electrodes.

SEE OR SEARCH THIS CLASS, SUBCLASS:

676,	for transistor with frequency multiplication or division.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 113-123 for frequency conversion or control.

[List of Patents for class 84 subclass 680]

680

With space discharging means:

This subclass is indented under subclass 678. Subject matter wherein the selecting circuit includes a device in which conduction of electrons takes place through a vacuum or gaseous medium.

SEE OR SEARCH THIS CLASS, SUBCLASS:

674,	for space discharging means with variable frequency.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 113-123 for frequency conversion or control.

[List of Patents for class 84 subclass 681]

681

Fundamental tone detection or extraction:

This subclass is indented under subclass 678. Subject matter wherein the fundamental or pitch is detected and used to activate or modify a musical system.

SEE OR SEARCH THIS CLASS, SUBCLASS:

616,	for fundamental tone detection or extraction with digital storage.
654,	for fundamental tone detection or extraction with digital combinational circuit.

[List of Patents for class 84 subclass 682]

682

Multiplexing or scanning:

This subclass is indented under subclass 678. Subject matter wherein the selecting circuits are assigned by time-division multiplexing or scanning.

SEE OR SEARCH THIS CLASS, SUBCLASS:

616,	for multiplexing or scanning with digital storage.
655,	for multiplexing or scanning with digital combinational circuit.

[List of Patents for class 84 subclass 683]

683

Noise reduction (e.g., error prevention, etc.):

This subclass is indented under subclass 678. Subject matter wherein circuitry is provided to reduce electrical noise, transients or unwanted disturbances.

SEE OR SEARCH THIS CLASS, SUBCLASS:

621,	for noise reduction (e.g., error prevention, etc.) with digital storage.

SEE OR SEARCH CLASS:

330,	Amplifiers, subclass 149 for noise, hum or distortion bucking introduced into signal channel.
381,	Electrical Audio Signal Processing Systems and Devices, subclasses 71.1-71.14 for acoustical noise or sound cancellation; subclasses 94.1-94.9 for noise or distortion suppression.

[List of Patents for class 84 subclass 684]

684

Priority or preference circuits:

This subclass is indented under subclass 678. Subject matter wherein a plurality of musical notes or keys are selected with a certain note or notes having precedence over others e.g., highest or lowest notes having priority, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

618,	for priority or preference circuits with digital storage.
656,	for priority or preference circuits with digital combinational circuit.

[List of Patents for class 84 subclass 685]

685

Transposition:

This subclass is indented under subclass 678. Subject matter wherein a musical piece is written or performed in a key other than the original or given key.

SEE OR SEARCH THIS CLASS, SUBCLASS:

619,	for transposition with digital storage.
657,	for transposition with digital combinational circuit.

[List of Patents for class 84 subclass 686]

686

Stops:

This subclass is indented under subclass 678. Subject matter wherein the circuit selects a musical voice, tone color, timbre or electrically simulated organ pipe sounds.

SEE OR SEARCH THIS CLASS, SUBCLASS:

620,	for stops with digital storage.

[List of Patents for class 84 subclass 687]

687

Force or velocity responsive:

This subclass is indented under subclass 678. Subject matter wherein the selecting circuit is responsive to the applied pressure, force or velocity.

SEE OR SEARCH THIS CLASS, SUBCLASS:

626,	for force or velocity responsive with digital storage.
658,	for force or velocity responsive with digital combinational circuit.

SEE OR SEARCH CLASS:

73,	Measuring and Testing, subclasses 488 -551 for speed or acceleration testing.
200,	Electricity: Circuit Makers and Breakers, Dig. 32 for speed responsive switching.
324,	Electricity: Measuring and Testing, subclass 160 for speed or velocity measuring.
338,	Electrical Resistors, subclass 69 for variable resistance key activation devices.
356,	Optics: Measuring and Testing, subclass 28 for velocity measuring utilizing a light detector.
362,	Illumination, subclass 802 for a position or condition responsive switch.

688	With magnetic selector:
	This subclass is indented under subclass 687. Subject matter wherein the selecting circuit includes a magnetic selector or selectors.

[List of Patents for class 84 subclass 689]

689

With capacitive selector:

This subclass is indented under subclass 687. Subject matter wherein the selecting circuit includes a capacitive selector or selectors.

SEE OR SEARCH CLASS:

200,	Electricity: Circuit Makers and Breakers, Dig. 1 for capacitive switching.

[List of Patents for class 84 subclass 690]

690

With variable resistance selector:

This subclass is indented under subclass 687. Subject matter wherein the selecting circuit includes a variable resistor or resistors.

SEE OR SEARCH CLASS:

338,	Electrical Resistors, subclasses 69+ for musical instrument playing key actuated variable resistance.

[List of Patents for class 84 subclass 691]

691

Noise reduction (e.g., error prevention, etc.):

This subclass is indented under subclass 671. Subject matter wherein circuitry is provided to reduce electrical noises, transients or unwanted disturbances.

SEE OR SEARCH THIS CLASS, SUBCLASS:

621,	for noise reduction (e.g., error prevention, etc.) with digital storage.
683,	for noise reduction (e.g., error prevention, etc.) with electric analog oscillators.

SEE OR SEARCH CLASS:

341,	Coded Data Generation and Conversion, subclass 94 for error detection or correction.

[List of Patents for class 84 subclass 692]

692

Tone synthesis or timbre control:

This subclass is indented under subclass 671. Subject matter wherein the harmonic content of a note is controlled or modified.

SEE OR SEARCH THIS CLASS, SUBCLASS:

622,	for tone synthesis or timbre control with digital storage.
659,	for tone synthesis or timbre control with digital combinational circuit.

SEE OR SEARCH CLASS:

307,	Electrical Transmission or Interconnection Systems, subclasses 106 -108 for waveform or waveshape determinative systems.
327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 100 -333 for miscellaneous signal converting, shaping, or generating.
333,	Wave Transmission Lines and Networks, subclass 28 for audio tone control.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 101 for automatic tone control; subclass 118 for signal processing of musical instruments; subclasses 101 through 103 for automatic tone or equalization of an audio signal.

[List of Patents for class 84 subclass 693]

693

Time varying or dynamic Fourier components:

This subclass is indented under subclass 692. Subject matter wherein the Fourier components are variable with respect to time.

SEE OR SEARCH THIS CLASS, SUBCLASS:

623,	for time varying or dynamic Fourier components with digital storage.

[List of Patents for class 84 subclass 694]

694

Modulation:

This subclass is indented under subclass 692. Subject matter wherein tones are synthesized or modified by varying a carrier wave in accordance with a modulation wave.

SEE OR SEARCH THIS CLASS, SUBCLASS:

624,	for modulation with digital storage.

[List of Patents for class 84 subclass 695]

695

Amplitude:

This subclass is indented under subclass 694. Subject matter wherein the carrier wave is amplitude modulated.

SEE OR SEARCH CLASS:

332,	Modulators, subclasses 149-182 for amplitude modulation.
375,	Pulse or Digital Communications, subclass 268 for amplitude modulation.

[List of Patents for class 84 subclass 696]

696

Angle (i.e., frequency or phase):

This subclass is indented under subclass 694. Subject matter wherein the carrier wave is angle (i.e., frequency or phase) modulated.

SEE OR SEARCH CLASS:

332,	Modulators, appropriate subclass for phase or frequency modulation.
375,	Pulse or Digital Communications, subclass 271 for angle modulation in systems using alternating or pulsating current.

[List of Patents for class 84 subclass 697]

697

Mixing:

This subclass is indented under subclass 692. Subject matter wherein two or more tones are combined to form a composite waveform.

SEE OR SEARCH THIS CLASS, SUBCLASS:

625,	for mixing with digital storage.
660,	for mixing with digital combinational circuit.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 113 -123 for a miscellaneous frequency mixing circuit.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 119 for audio system mixers, per se.

698	Partials (i.e., harmonics):
	This subclass is indented under subclass 697. Subject matter wherein two or more partials or harmonics are combined to form a composite waveform.

[List of Patents for class 84 subclass 699]

699

Filtering:

This subclass is indented under subclass 692. Subject matter wherein a desired waveform is obtained by removing one or more partials or harmonics.

SEE OR SEARCH THIS CLASS, SUBCLASS:

661,	for filtering with digital combinational circuit.

SEE OR SEARCH CLASS:

307,	Electrical Transmission or Interconnecting Systems, subclass 105 for harmonic filter or neutralizer.
333,	Wave Transmission Lines and Networks, subclass 167 for frequency domain filters using lumped parameters; subclass 186 for electromechanical type filters.

700	Variable:
	This subclass is indented under subclass 699. Subject matter wherein the partials or harmonics to be removed can be varied in accordance with a desired timbre or color.

[List of Patents for class 84 subclass 701]

701

Expression or special effects:

This subclass is indented under subclass 671. Subject matter for providing an indication of feeling or artistic execution to the musical tones.

SEE OR SEARCH THIS CLASS, SUBCLASS:

626,	for expression or special effects with digital storage.
662,	for expression or special effects with digital combinational circuit.

[List of Patents for class 84 subclass 702]

702

Envelope shaping (e.g., attack, decay, sustain or release, etc.):

This subclass is indented under subclass 701. Subject matter for providing or modifying an amplitude contour of an activated tone.

SEE OR SEARCH THIS CLASS, SUBCLASS:

627,	for envelope shaping, e.g., attack, decay, sustain or release, etc., with digital storage.
663,	for envelope shaping, e.g., attack, decay, sustain or release, etc., with digital combinational circuit.

SEE OR SEARCH CLASS:

327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 306 -333 for signal shaping by controlling the amplitude thereof.
331,	Oscillators, subclass 182 for amplitude control of an oscillator.

[List of Patents for class 84 subclass 703]

703

Attack and decay:

This subclass is indented under subclass 702. Subject matter for producing or modifying only the attack and decay of an activated tone.

SEE OR SEARCH THIS CLASS, SUBCLASS:

627,	for envelope shaping with digital storage.
663,	for envelope shaping with digital combinational circuit.

[List of Patents for class 84 subclass 704]

704

Portamento or glissando:

This subclass is indented under subclass 701. Subject matter for producing an audible glide from one tone to a second tone.

SEE OR SEARCH THIS CLASS, SUBCLASS:

628,	for portamento or glissando with digital storage.

[List of Patents for class 84 subclass 705]

705

Tremolo:

This subclass is indented under subclass 701. Subject matter providing for rapid iteration of or a modulation in the amplitude of a note at subaudio frequencies.

SEE OR SEARCH THIS CLASS, SUBCLASS:

629,	for tremolo with digital storage.

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclass 62 for tremolo or vibrato.

[List of Patents for class 84 subclass 706]

706

Vibrato:

This subclass is indented under subclass 701. Subject matter providing a modulation in the frequency or phase of a note at subaudio frequencies.

SEE OR SEARCH THIS CLASS, SUBCLASS:

629,	for vibrato with digital storage.

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclass 62 for tremolo or vibrato.

[List of Patents for class 84 subclass 707]

707

Reverberation:

This subclass is indented under subclass 701. Subject matter providing for time delays that simulate a plurality of reflections of a given tone, e.g., echo, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

630,	for reverberation with digital storage.

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclass 63 for reverberators, per se.

[List of Patents for class 84 subclass 708]

708

Chorus, ensemble, or celeste:

This subclass is indented under subclass 701. Subject matter providing for the combining of a slightly detuned tone with the original tone.

SEE OR SEARCH THIS CLASS, SUBCLASS:

631,	for chorus, ensemble, or celeste with digital storage.
664,	for chorus, ensemble, or celeste with digital combinational circuit.

SEE OR SEARCH CLASS:

381,	Electrical Audio Signal Processing Systems and Devices, subclass 89 for driven speaker systems to produce vibrato or chorus effects.

709	Trill:
	This subclass is indented under subclass 701. Subject matter wherein the rapid alternation of two tones either a whole or a half tone apart.

[List of Patents for class 84 subclass 710]

710

Chiff or percussive transients:

This subclass is indented under subclass 701. Subject matter wherein transients are introduced into the initial sounding of the tone during the initial portion of the envelope to simulate the hiss or noise of an organ pipe.

SEE OR SEARCH THIS CLASS, SUBCLASS:

632,	for chiff or percussive transients with digital storage.

[List of Patents for class 84 subclass 711]

711

Loudness control:

This subclass is indented under subclass 701. Subject matter wherein amplitude or volume of the musical tones may be regulated.

SEE OR SEARCH THIS CLASS, SUBCLASS:

633,	for loudness control with digital storage.
665,	for loudness control with digital combinational circuit.

[List of Patents for class 84 subclass 712]

712

Accompaniment:

This subclass is indented under subclass 671. Subject matter for providing a musical support or background.

SEE OR SEARCH THIS CLASS, SUBCLASS:

610,	for accompaniment with note sequence of digital memory circuit.
634,	for accompaniment with digital memory circuit.
650,	for accompaniment with note sequence of digital combinational circuit.
666,	for accompaniment with digital combinational circuit.

[List of Patents for class 84 subclass 713]

713

Rhythm:

This subclass is indented under subclass 712. Subject matter for creating or modifying the timing intervals of a music piece.

SEE OR SEARCH THIS CLASS, SUBCLASS:

611,	for rhythm with note sequence of digital memory circuit.
635,	for rhythm with digital memory circuit.
651,	for rhythm with note sequence of digital combinational circuit.
667,	for rhythm with digital combinational circuit.

[List of Patents for class 84 subclass 714]

714

Tempo control:

This subclass is indented under subclass 713. Subject matter wherein the rate or speed of rhythm is variable.

SEE OR SEARCH THIS CLASS, SUBCLASS:

612,	for tempo control with note sequence of digital memory circuit.
636,	for tempo control with digital memory circuit.
652,	for tempo control with note sequence of digital combinational circuit.
668,	for tempo control with digital combinational circuit.

[List of Patents for class 84 subclass 715]

715

Chords:

This subclass is indented under subclass 712. Subject matter wherein a plurality of notes are played simultaneously.

SEE OR SEARCH THIS CLASS, SUBCLASS:

613,	for chords with note sequence of digital memory circuit.
637,	for chords with digital memory circuit.
669,	for chords with digital combinational circuit.

[List of Patents for class 84 subclass 716]

716

Arpeggio:

This subclass is indented under subclass 712. Subject matter wherein the notes of a chord are played in sequence.

SEE OR SEARCH THIS CLASS, SUBCLASS:

638,	for arpeggio with digital storage.

[List of Patents for class 84 subclass 717]

717

Reiteration:

This subclass is indented under subclass 712. Subject matter wherein plural tones are repetitively played in sequence one at a time.

SEE OR SEARCH THIS CLASS, SUBCLASS:

614,	for reiteration with digital storage.

[List of Patents for class 84 subclass 718]

718

Constructional details:

This subclass is indented under subclass 671. Subject matter including mechanical features of the musical instrument.

SEE OR SEARCH THIS CLASS, SUBCLASS:

2,	for dealing with specifics of musical instrument construction.
644,	for construction details with digital storage.
670,	for construction details with digital combinational circuit.

[List of Patents for class 84 subclass 719]

719

Keyboard:

This subclass is indented under subclass 718. Subject matter wherein the mechanical feature is a keyboard or a fret-board.

SEE OR SEARCH THIS CLASS, SUBCLASS:

691,	for noise reduction with electric analog oscillators.

SEE OR SEARCH CLASS:

341,	Coded Data Generation and Conversion, subclasses 22 -34 for code selecting devices, e.g., keyboards or keypads, etc.

[List of Patents for class 84 subclass 720]

720

Keyswitch structure:

This subclass is indented under subclass 718. Subject matter wherein the mechanical feature is a keyswitch.

SEE OR SEARCH CLASS:

200,	Electricity: Circuit Makers or Breakers, appropriate subclasses for specific switch construction details.

[List of Patents for class 84 subclass 721]

721

Foot control:

This subclass is indented under subclass 718. Subject matter wherein the mechanical feature is a foot controlled device.

SEE OR SEARCH CLASS:

200,	Electricity: Circuit Makers or Breakers, subclass 86.5 for foot controlled switches, per se.

[List of Patents for class 84 subclass 722]

722

Fret control:

This subclass is indented under subclass 671. Subject matter wherein oscillators are controlled via a stringed musical instrument fingerboard, e.g., switches on the guitar fingerboard, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

646,	for fret control with digital storage.

[List of Patents for class 84 subclass 723]

723

Transducers:

This subclass is indented under subclass 600. Subject matter including means which converts energy other than electrical into electrical energy.

SEE OR SEARCH CLASS:

29,	Metal Working, subclass 594 for methods of making an acoustic transducer.
178,	Telegraphy, subclasses 47 and 48 for electrical signaling systems in which vibrating means such as reeds, tuning forks, and diaphragms are utilized in transmitting or receiving messages or signals.
310,	Electrical Generator or Motor Structure, appropriate subclasses for general application of converting mechanical motion to electrical currents or potentials.
322,	Electricity: Single Generator Systems, appropriate subclasses for general application of converting mechanical motion to electrical currents or potential, particularly subclass 3 for reciprocating or oscillating generator systems.
704,	Data Processing: Speech Signal Processing, Linguistics, Language Translation, and Audio Compression/Decompression, subclasses 200 through 504for speech signal processing, or bandwidth, or time compression, or expansion of an audio signal.

[List of Patents for class 84 subclass 724]

724

Photoelectric:

This subclass is indented under subclass 723. Subject matter including means which converts varying light intensity into varying electric currents or potential.

SEE OR SEARCH THIS CLASS, SUBCLASS:

639,	for photoelectric with digital storage.

SEE OR SEARCH CLASS:

250,	Radiant Energy, subclasses 200 -239 for photocell electric circuits and photocell apparatus; subclasses 206-214.1 for photocell with coded record; subclasses 232-233 for photocells with light chopper type.
330,	Amplifiers, subclass 59 for amplifiers including light controlled or light activated means.
369,	Dynamic Information Storage or Retrieval, subclasses 86-92 for storage or retrieval of audio signals.

[List of Patents for class 84 subclass 725]

725

Electromagnetic:

This subclass is indented under subclass 723. Subject matter including means which converts varying magnetic flux into varying electric currents or potentials.

SEE OR SEARCH THIS CLASS, SUBCLASS:

641,	for magnetic with digital storage.

SEE OR SEARCH CLASS:

29,	Metal Working, subclasses 602.1 -609.1 for methods of manufacturing an electromagnet, transformer, or inductor.
336,	Inductor Devices, appropriate subclasses for inductive reactors and transformers which are provided with fixed or movable elements, e.g., having a moving armature to modify the impedance of an inductive reactor, etc.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 115 for magnetic microphone.

[List of Patents for class 84 subclass 726]

726

String:

This subclass is indented under subclass 725. Subject matter wherein the varying magnetic flux is caused by a moving string.

SEE OR SEARCH THIS CLASS, SUBCLASS:

7	through 82, 172, 173-329, for miscellaneous stringed instruments.

727	With adjustable means:
	This subclass is indented under subclass 726. Subject matter wherein the transducer or a component thereof is adjustable relative to a string.

[List of Patents for class 84 subclass 728]

728

Noise reduction (e.g., error prevention, etc.):

This subclass is indented under subclass 726. Subject matter wherein circuitry is provided to reduce electrical noises, transients, or unwanted disturbances.

SEE OR SEARCH THIS CLASS, SUBCLASS:

621,	for noise reduction with digital storage.
683,	for noise reduction with selecting circuit of analog oscillators.
691,	noise reduction with analog oscillators.

SEE OR SEARCH CLASS:

375,	Pulse or Digital Communications, subclasses 284 and 285 for antinoise or distortion systems using alternating or pulsating current.
381,	Electrical Audio Signal Processing Systems and Devices, appropriate subclass acoustical noise or sound cancellation; subclasses 94.1 -94.9 for noise or distortion suppression.

[List of Patents for class 84 subclass 729]

729

Reed:

This subclass is indented under subclass 725. Subject matter wherein the varying magnetic flux is caused by a moving elongated flexural strip or bar with a relatively large length to width ratio.

SEE OR SEARCH THIS CLASS, SUBCLASS:

402	through 410, and 411-421, for miscellaneous musical instruments employing rigid vibrators.

[List of Patents for class 84 subclass 730]

730

Piezoelectric:

This subclass is indented under subclass 723. Subject matter wherein a varying mechanically stressed crystal causes a varying current or voltage.

SEE OR SEARCH CLASS:

29,	Metal Working, subclass 25.35 for methods of making a piezoelectric device.
310,	Electrical Generator or Motor Structure, subclasses 311 -371 for piezoelectric elements and devices.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 114 for piezoelectric microphone.

[List of Patents for class 84 subclass 731]

731

String:

This subclass is indented under subclass 730. Subject matter wherein the varying mechanical stress is caused by a string.

SEE OR SEARCH THIS CLASS, SUBCLASS:

7	through 82, 172 and 173-329, for miscellaneous stringed instruments.
726,	for string with electromagnetic transducer.

[List of Patents for class 84 subclass 732]

732

Reed:

This subclass is indented under subclass 730. Subject matter wherein the varying mechanical stress is caused by an elongated flexural strip or bar with a relatively large length to width ratio.

SEE OR SEARCH THIS CLASS, SUBCLASS:

402	through 410, and 411-421, for miscellaneous musical instruments employing rigid vibrators.
729,	for reed with electromagnetic transducer.

[List of Patents for class 84 subclass 733]

733

Capacitive:

This subclass is indented under subclass 723. Subject matter wherein a varying capacitance produces a varying electric current or potential.

SEE OR SEARCH CLASS:

200,	Electricity: Circuit Makers and Breakers, subclass 181 for electrostatic switches.
361,	Electricity: Electrical Systems and Devices, subclasses 271 -330 for electrostatic capacitors.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 113 for electrostatic microphone.

[List of Patents for class 84 subclass 734]

734

Strain gauge:

This subclass is indented under subclass 723. Subject matter wherein a varying force, tension or pressure is converted into a varying electrical current or potential.

SEE OR SEARCH CLASS:

29,	Metal Working, subclass 621.1 for methods of making strain gauges.
338,	Electrical Resistors, subclasses 2-6 for strain gauges; subclass 69 for variable resistors controlled by musical instrument playing keys.

[List of Patents for class 84 subclass 735]

735

Tone synthesis or timbre control:

This subclass is indented under subclass 723. Subject matter wherein the harmonic content of a note is controlled or modified.

SEE OR SEARCH THIS CLASS, SUBCLASS:

622,	for tone synthesis or timbre control with digital storage.
659,	for tone synthesis or timbre control with digital combinational circuit.
692,	for tone synthesis or timbre control with electric analog oscillators.

SEE OR SEARCH CLASS:

307,	Electrical Transmission or Interconnection Systems, subclass 3 for circuits in which different frequencies are superimposed; subclasses 106-108 for waveform or waveshape determinative systems.
310,	Electrical Generator or Motor Structure, appropriate subclasses for dynamoelectric frequency changers.
327,	Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, subclasses 100 -333 for miscellaneous signal converting, shaping, or generating, and particularly subclasses 113-123 for miscellaneous harmonic generators.
331,	Oscillators, appropriate subclasses for general harmonic generators.
333,	Wave Transmission Lines and Networks, subclass 28 for audio tone controls.
363,	Electric Power Conversion Systems, subclasses 157 -177 for electric power frequency conversion systems.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 101 for automatic tone control; subclass 118 for signal processing of musical instruments, per se; subclasses 101 through 103 for automatic tone control or equalization of audio signals.

[List of Patents for class 84 subclass 736]

736

Filtering:

This subclass is indented under subclass 735. Subject matter wherein a desired waveform is obtained by removing one or more partials or harmonics.

SEE OR SEARCH THIS CLASS, SUBCLASS:

661,	for filtering with digital combinational circuit.
699	through 700, for filtering with electric analog oscillators.

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327,	Miscellaneous Active Electrical on linear Devices, Circuits, and Systems, subclass 311 for transient limiting utilizing a filter and subclasses 552-559 for unwanted signal suppression with an active filter.
330,	Amplifiers, subclass 303 for filters included or in conjunction with an amplifier.
333,	Wave Transmission Lines and Networks, subclasses 167 -185 for lumped parameter filters; subclass 165 for frequency or time domain filters and delay lines; subclass 166 for time domain filters.
708,	Electrical Computers: Arithmetic Processing and Calculating, subclasses 300 -323 for digital filters.

[List of Patents for class 84 subclass 737]

737

Expression or special effects:

This subclass is indented under subclass 723. Subject matter for providing "feeling" or artistic execution to the musical tones.

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33	through 64, for expression mechanism.
157,	for modified expression.
164,	for expression and tempo marks.
216	through 233, for expression devices.
313,	for tremolo devices.
374,	for fan tremolo devices.
626,	for expression or special effects with digital storage.
662,	for expression or special effects with digital combinational circuit.
701,	for expression or special effects with electric analog oscillators.

[List of Patents for class 84 subclass 738]

738

Envelope shaping (e.g., attack, decay, sustain or release, etc.):

This subclass is indented under subclass 737. Subject matter for providing or modifying the contour of an activated tone.

SEE OR SEARCH THIS CLASS, SUBCLASS:

627,	for envelope shaping with digital storage.
663,	for envelope shaping with digital combinational circuit.
702,	for envelope shaping with electric analog oscillators.

[List of Patents for class 84 subclass 739]

739

Tremolo:

This subclass is indented under subclass 737. Subject matter providing for rapid iteration of or a modulation in the amplitude of a note at sub-audio frequencies.

SEE OR SEARCH THIS CLASS, SUBCLASS:

629,	for tremolo with digital storage.
705,	for tremolo with electric analog oscillators.

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332,	Modulators, subclasses 149 through 182for amplitude modulation.
375,	Pulse or Digital Communications, subclasses 268 -270 for amplitude modulation.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 62 for general purpose tremolo.

[List of Patents for class 84 subclass 740]

740

Vibrato:

This subclass is indented under subclass 737. Subject matter providing a modulation in the frequency or phase of a note at sub-audio frequencies.

SEE OR SEARCH THIS CLASS, SUBCLASS:

629,	for vibrato with digital storage.
706,	for vibrato with electric analog oscillators.

SEE OR SEARCH CLASS:

331,	Oscillators, subclass 178 for providing vibrato in the oscillator output frequency.
332,	Modulators, subclasses 117-143 for frequency modulation.
375,	Pulse or Digital Communications, subclasses 271 -284 for angle modulation.
381,	Electrical Audio Signal Processing Systems and Devices, subclass 62 for general purpose vibrato.

[List of Patents for class 84 subclass 741]

741

Loudness control:

This subclass is indented under subclass 737. Subject matter wherein amplitude or volume of the musical tone may be regulated.

SEE OR SEARCH THIS CLASS, SUBCLASS:

633,	for loudness control with digital storage.
665,	for loudness control with digital combinational circuit.
711,	for loudness control with electric analog oscillators.

[List of Patents for class 84 subclass 742]

742

Selecting circuits:

This subclass is indented under subclass 723. Subject matter including a circuit which selects a musical parameter, e.g., pitch or timbre, etc.

SEE OR SEARCH THIS CLASS, SUBCLASS:

615,	for selecting circuits with digital storage.
653,	for selecting circuits with digital combinational circuit.
678,	for selecting circuits with electric analog oscillators.