Regarding producing sound, this subclass covers producing sound with a frequency determined by the frequency of the electrical signal applied to the transducer, whereas G10K covers producing sounds with frequency not so determined.

Details of transducers, loudspeakers or microphones.

Further detail is covered by the Indexing Code group H04R 2201/003 listed below. Classification is obligatory.

Example for a loudspeaker transducer (the number of windings of the 15 coils ranges from 2⁰-2¹⁴)

Example for a microphone transducer:

Casings, cabinets for transducers, their manufacture, their support, or mountings for transducers therein.

Further detail is covered by the subgroups of Indexing Code group H04R 2201/02 listed below. Classification is obligatory.

A mesh or grating covering the loudspeaker transducer or a sound path leading to the loudspeaker transducer

Means to hold a loudspeaker casing for and during use

As shown in the figure circuitry (81) can be mounted inside the microphone (80)

Connection or contacting arrangements specially adapted to transducers, loudspeakers or headphones.

In the example the tinsel wire 145 is prevented from contacting the diaphragm during vibration, by ring structure 150.

In the example, the terminal 30 is prevented from bending too much during mounting, by stopper 29.

Further detail is covered by the subgroup of Indexing Code group H04R 2420/09 listed below. Classification is obligatory.

Microphones, mouthpieces or attachments therefor, e.g. spiders or microphone booms, or protective screens therefor, e.g. all weather or wind screens.

Further detail is covered by the subgroup of Indexing Code group.

Further detail is covered by Indexing Code group H04R 2410/07. Classification is obligatory.

Further detail is covered by the subgroups of Indexing Code group H04R 2460/09 and H04R 2460/11 listed below. Classification is obligatory.

Adaptations to earpieces to enable charging.

For example:

For example:

A stereophonic earphone with two earpieces each with a cable (4,5). The cable is wound on a spool (8) for storing the cables when the earphone is not in use.

For example:

A stereophonic headphone with a U-shaped slider (8) to adjust the length of the cable.

For example (electronic switch/control elements)

For example (mechanical control element):

Earphone wherein the frequency response can be changed by changing (with slide 130) the number of holes (124) that are open/closed. Please take note of precedence rule referring to H04R 1/28.

For example:

Earpiece support 30 is used to attach headset to the ear. The arms 31 of support 30 are rotatable around hinge H.

Methods of manufacture or assembling as well as the way devices are assembled or constructed

For example:

Example (ear hook):

Example (headband):

Example (headband):

For example: (positioning of the transducers (4, 5, 6) in the earpiece)

For example: (mounting of the loudspeakers mounted on the head support (in figure only the left side: left front 22L and left rear 24L both ported to the left ear)

For example:

A personal noise exposure dose meter integrated in an active hearing protective communications earplug, comprising a main section 1 containing two microphones an outer microphone M1 and an inner microphone M2, and a sound generator SG, which are used for active noise control. A sealing section 2 is attached to the main section. An acoustic transmission channel T1 connects microphone M2 to the inner portion of the meatus 3. Microphone M2 therefore picks up the sound present in the meatus 3, just outside the eardrum (tympanum) 4. An acoustic transmission channel T2 connects sound generator SG to the inner portion of the meatus 3. The sound generator SG may provide audible information to the user, in form of warning signals or synthetic speech.

For example:

Noise reduction using feedback (23):

Noise reduction using feedforward (33).

Further detail is covered by Indexing Code group H04R 2460/01. Classification is obligatory.

Further detail is covered by Indexing Code groups H04R 2201/103, H04R 2201/105, H04R 2201/107, H04R 2201/109, H04R 2420/07, H04R 2420/09, H04R 2460/03, H04R 2460/05, H04R 2460/07, H04R 2460/13, H04R 2460/15 and H04R 2460/17. Classification is obligatory.

Arrangements where the focus lies in the way the desired frequency characteristic is obtained

If a directivity effect is also addressed classification in H04R 1/32 or subgroups as additional information is required as well

Transducer enclosure modified by provision of mechanical or acoustic impedances to achieve a desired frequency or phase response, e.g. enclosures:

Transducer mountings or enclosures modified to reduce undesired resonances, i.e. standing waves within enclosure, or of vibrations, i.e. of the enclosure itself, by e.g.:

Applications of the mountings or enclosures for loudspeaker transducers is to be classified in the appropriate subgroup with title "{for loudspeaker transducers}";

Further detail is covered by the subgroup of Indexing Code group H04R 2201/029. Classification is obligatory.

Example for porous material (12) for virtual volume increase, to improve bass response:

Example for porous carbon material (20) for virtual volume increase, to improve bass response, membrane (22) is to prevent moisture from reaching the porous carbon material; membrane acoustically transparent)

The use of porous materials in loudspeaker enclosures for equivalent volume increase is classified under H04R 1/2803). For mid- and high-frequencies the porous material works as a damping material too. Thus classification in H04R 1/2876 or Indexing Code may be required if this aspect is addressed as well.

Example (for H04R 1/2811): movable side wall (4) for varying volume to adapt frequency response:

Example (for H04R 1/2811): left-hand figure amplified bass, and right-hand figure normal bass:

Examples (for H04R 1/2826):

Vent with variable length:

Shape of the vent:

Shape and structure of the vent

For example (for H04R 1/2842):

(vent 9 is not tuned to the wavelength)

Example 1st classification rule (the vent is replaced by a passive membrane):

Example 2nd classification rule (vent replaced by tube tuned to the wavelength)

Enclosures using an acoustic labyrinth or a transmission line. The acoustic labyrinth or the transmission line can be open or closed.

For example (for H04R 1/2857):

The length of the top tubular part is tuned to the wavelength.

Acoustic labyrinths or transmission lines (invention) and being used in a bandpass type enclosure is classified in H04R 1/2853 or H04R 1/2857 (invention information), but H04R 1/2838 or H04R 1/2842 (additional information) is to be given as well.

Enclosures using a back-loaded horn. The horn has an aperture surface area that increases with distance from the transducer along the horn axis.

Reduction of undesired resonances not covered by its subgroups, e.g. by means of Helmholtz resonators

For example (for H04R 1/2888):

Stiffening panels inside the enclosure

Shape of the enclosure to reduce reflexions within the enclosure

For example (for H04R 1/2896): DE202004017450U (rubber transducer mounting), US2005152570.

For example (for H04R 1/2896):

Rubber transducer mounting (5) combined with flexible cables (3):

Elastic mounting (20) with dampening buffer element (30)

Combinations of transducers with front-loaded horns; Enclosures using front-loaded horns, the acoustic horns predominantly being characterised by the mechanical matching, even though a directivity effect is also present

The horn has an aperture surface area that increases with distance from the transducer along the horn axis

For example:

In the example shown on the left the exponential area increase is obtained by the combination of a cylindrical housing (1) with a flat sloped plate (3).

Further detail is covered by the subgroup of Indexing Code group H04R 2400/13 listed below. Classification is obligatory.

Arrangements where the focus lies in the way the desired directional characteristic is obtained

Sound reflecting, diffracting, directing or guiding means, e.g. horns to obtain a desired directivity characteristic, acoustic lenses, tubes, or phase plugs

For example: (horn (top figure) used to obtain predetermined directivity (lower figures)

For example: (plurality of plates (210) functioning as an acoustic lens).

Further detail is covered by Indexing Code group H04R 2201/34 listed below. Classification is obligatory.

For example:

Such an aperture functions as an acoustic lens

Further detail is covered by the subgroups of Indexing Code group H04R 2201/40. Classification is obligatory.

Further detail is covered by the subgroup of Indexing Code group H04R 2410/05. Classification is obligatory.

Circuits for transducers, e.g.:

Further detail is covered by the subgroups of Indexing Code groups H04R 2201/401, H04R 2201/403, H04R 2201/405, H04R 2203/12, H04R 2410/07, H04R 2420/01, H04R 2420/03, H04R 2420/05, H04R 2430/01 and H04R 2430/03. Classification is obligatory.

Further detail is covered by Indexing Code groups H04R 2410/01, H04R 2410/05 and H04R 2430/20 and its subgroups. Classification is obligatory.

Further detail is covered by Indexing Code groups H04R 2203/12 and H04R 2430/20. Classification is obligatory.

Spatial or constructional arrangements of loudspeakers or of electro-acoustic devices for stereophonic purposes or specific circuit arrangements therefor, e.g.

Spatial or constructional arrangements of loudspeakers or loudspeaker transducers for stereophonic reproduction, e.g.

Further detail is covered by Indexing Code groups H04R 2205/021, H04R 2205/022, H04R 2205/024 and H04R 2205/026. Classification is obligatory.

Spatial or constructional arrangements of microphones or microphone transducers for stereophonic sound capture.

For example (dummy head):

For example (sound field microphone):

For example: segmented headband for easy storage of the headphone

For example: (head support with loudspeakers mounted thereon (in figure only the left side: left front speaker 22L and left rear speaker 24L both ported to the left ear)

Further detail is covered by Indexing Code groups H04R 2205/041, subgroups of H04R 2420/00, and H04R 2430/01. Classification is obligatory.

Further detail is covered by Indexing Code groups H04R 2207/021, H04R 2231/001, H04R 2231/003 and H04R 2307/021 - H04R 2307/029. Classification is obligatory.

Further detail is covered by Indexing Code groups H04R 2440/01 and H04R 2440/07. Classification is obligatory.

For example: Upon excitation of diaphragm 1 by piezoelectric exciter 15 the diaphragm generating bending wave in itself and eventually produces sound by resonating.

Further detail is covered by Indexing Code groups H04R 2440/03 and H04R 2440/05. Classification is obligatory.

For example: (dome 52).

For example: DE202007016414 (air motion transformer).

For example: ribs to provide rigidity to the central part of the loudspeaker diaphragm

For example: air motion transformer (AMT) with a meander shaped diaphragm and air pockets (6). Upon energising the transformer (current through conductors 2) and due to the magnetic field perpendicular to the current, the air in the pockets is pushed out or pulled in, thus producing sound.

For example: diaphragm is mounted to the frame (26) by surround (29) which is connected to the membrane (27) within its periphery (at 200)

For example: membrane (2) is extended to form outer suspension (21), whose elastic properties are adapted by the elastic layer (22).

For example: membrane (34) divided in a suspension part (34A, 34B) and a central sound producing part (34C)

For example:

Further detail is covered by Indexing Code groups H04R 2231/001, H04R 2231/003, H04R 2307/201 - H04R 2307/207. Classification is obligatory.

For example: Microphone comprising a vibrating plate (12) with polar ring which is clamped via a spacer (13) between base (14, 16) and the casing (102). Groove 102h is formed to prevent deformation of the polar ring which would negatively affect the acoustic properties membrane (2) is extended to form outer suspension (21), whose elastic properties are adapted by the elastic layer (22).

For example: EP0330423.

For example: tensioning by springs 5'

For example: damping by elastic material 27

For example: sound producing diaphragm provided with a damping layer (12) to dampen vibration in the diaphragm

Transducers of moving-coil, moving-strip, or moving-wire type, e.g.

Further detail is covered by Indexing Code group H04R 2201/003 and the subgroups of Indexing Code group H04R 2440/00. Classification is obligatory.

Further detail is covered by Indexing Code groups H04R 2209/021 - H04R 2209/027 and the subgroups of Indexing Code group H04R 2400/00. Classification is obligatory.

Further detail is covered by the subgroups of Indexing Code groups H04R 2209/041 and H04R 2209/043 listed below. Classification is obligatory.

For example: the inner suspension (13) is formed with leg portions (13b, 13c) having equal length, to prevent lateral vibration of the bobbin (8). Thus excursion of suspension and thus of the diaphragm can be increase without increasing the diameter of the inner suspension.

Mounting of the voice coil or the bobbin on which the voice coil is wound

For example: the connection between bobbin (8) and diaphragm (2) is provided with a groove, which is filled with glue to strengthen the connection.

Example: bobbin assembly (355) removably mounted to the inner circumference of the diaphragm (310). Thus replacement of damaged assembly requires minimal effort.

Example: bobbin (140) is mounted at its top directly to outer suspension and in the middle via bridge (160). Thus the bobbin is prevented from bending.

Further detail is covered by Indexing Code group and by H04R 2400/13. Classification is obligatory.

Transducers for loudspeakers wherein the voice coil is directly mounted to vibrating diaphragm and the magnetic circuit is floating but suspended with respect to the diaphragm and voice coil.

For example: body sensed speaker, that can be placed in e.g. waistcoats, cushions, matrasses, belts

For example: exciter for distributed mode loudspeakers (DML)

Further detail is covered by Indexing Code group H04R 2400/07. Classification is obligatory.

Further detail is covered by the subgroups of Indexing Code groups H04R 2400/01, H04R 2400/03, and H04R 2440/01 - H04R 2440/07.

For example:

The voice coil (2) is static. Upon energising the magnets (4-6) move.

Example of a hearing aid receiver:

Armature 136 has a fixed (146) and a movable arm (144). When coils 134 is energised, movable arm 144 moves and drives membrane (118) via a linkage 138, thus producing sound.

Example of a bone conduction speaker:

Voice coil 30 is mounted directly to base plate 14 which is part of the transducer frame. The magnetic circuit (yoke 22, magnet 24, base plate 26) is movably attached to the frame 12 via damper 20, such that upon energising the voice coil the armature moves.

Further detail is covered by Indexing Code group H04R 2400/07 and H04R 2400/11. Classification is obligatory.

Transducers for loudspeakers or microphones, in which the membrane is part of the magnetic circuit.

For example:

Further detail is covered by the subgroup of Indexing Code group H04R 2400/11 listed below. Classification is obligatory.

In the example shown in the figure below a configuration of the magnetostrictive actuator 103 is presented. The magnetostrictive actuator 103 has a rod-like magnetostrictive element 151 that is displaced along its extension direction, a solenoid coil 152 for generating a magnetic field, which is positioned around this magnetostrictive element 151, a driving rod 103a as driving member, which is connected to an end of the magnetostrictive element 151 and transmits any displacement output of the magnetostrictive actuator 103, and a container 154 that contains the magnetostrictive element 151 and the solenoid coil 152 therein.

Further detail is covered by Indexing Code group H04R 2201/003, H04R 2217/01, H04R 2400/03 and H04R 2400/11. Classification is obligatory.

Further detail is covered by Indexing Code group H04R 2201/003, H04R 2217/01, H04R 2400/03, H04R 2400/11 and the subgroups of Indexing Code group H04R 2440/00. Classification is obligatory.

Further detail is covered by Indexing Code group H04R 2410/03. Classification is obligatory.

Further detail is covered by Indexing Code groups H04R 2400/11 and H04R 2410/03. Classification is obligatory.

Acoustic transducers using solid state devices and not covered by H04R 9/00 - H04R 21/00

The signal processing is done external to the hearing aid part that is in the ear (as for example shown in the figure)

For example testing of the functioning of an amplifier in a hearing aid (see figure). Switching circuit 20 measures a time period T, and interrupts the signal from the microphone 10 once every such period T. The interruption, or test time interval, lasts for another measured time segment t where t is less than T. During the interruption, the switching circuit 20 transmits the signal from the signal generator 22 to the hearing aid amplifier 12 to act as a test signal. Difference detector 24 detects malfunction of the amplifier. Difference detector 34 low battery status.

Further detail is covered by Indexing Code group H04R 2460/15. Classification is obligatory.

Example of a self-diagnosis system with which the transducers and other component can be checked, see figure.

Further detail is covered by Indexing Code subgroup H04R 2225/39. Classification is obligatory.

For example:

For example:

Mechanical aspects, e.g. orientation, relative placement, of acoustic transducers in hearing aids to obtain a desired directional characteristic.

For example microphone openings (17A-17C) arranged along a straight line (see figure):

For example microphones (8a,8b) mounted in a BTE housing and additional microphones (8c, 8d) mounted in a lever (4) which can be swung away from the housing to adapt the directivity of the hearing aid.

The mere fact that more than one microphone is used to obtain a desired directivity need not be classified, especially if H04R 25/407 has to be given anyway (cf. the first 2 EXAMPLES given for H04R 25/407).

Further detail is covered by Indexing Code group H04R 2410/01. Classification is obligatory.

For example:

Further detail is covered by Indexing Code groups H04R 2410/01 and H04R 2430/20 listed below. Classification is obligatory.

Example for input selection:

Example for mixing:

General analog or digital signal processing in hearing aid not provided for in H04R 25/00 or its subgroups.

External connection for the purpose of data exchange between hearing aids, e.g. binaural hearing aids, or between hearing aid and external device, e.g. telecoil, remote control, or for charging of batteries in hearing aids

Example for wirelessly charging accumulators in a hearing aid (see figure)

Binaural control, e.g. control of one hearing aid in dependence of the other; Data exchange between hearing aids to enable binaural control, e.g. type of data, timing, ...

The mere fact that binaural control of data exchange is wired or wireless needs not be classified.

Electric hearing aids using wireless connection for the transmission audio representative data, e.g. T-coils, FM receivers (see e.g. the figure below)

Binaural hearing aids (invention) are not to be classified in this group but in H04R 25/552. No classification in H04R 25/554 (as invention of additional information) is in principle needed.

Example for an ITE hearing aid connected to a programmer (5):

Example for a BTE hearing aid additionally provided with an FM receiver (3):

Connection between the BTE housing and the earmould via an earhook is not to be classified here but in H04R 25/60 in combination with H04R 2225/0213.

Arrangements for mounting or interconnection of hearing aid parts.

Example: Details of mounting of ear tip (11) via tube (21 to BTE housing (30):

Further detail is covered by Indexing Code subgroups H04R 2225/0213, H04R 2225/49, H04R 2225/59, H04R 2225/61, and H04R 2225/67. Classification is obligatory.

Arrangements for mounting or interconnection of batteries in hearing aids

Arrangements for mounting or interconnection of transducers in hearing aids

Mounting or interconnection aspects of implantable hearing aid transducers

Interconnection or mounting of electrical aspects of implantable hearing aid transducers

Example CIC: housing (15) and ear tip (18)

Example ITE: housing (15) and ear mould (21)

Example BTE: housing (17) and ear tip (20).

Further detail is covered by Indexing Code group H04R 2225/77. Classification is obligatory.

For examples, please see H04R 25/65.

Further detail is covered by Indexing Code groups H04R 2460/09 and H04R 2460/11. Classification is obligatory.

Means for protecting electric components, e.g. receivers, microphones, in hearing aids against e.g. earwax, oil, moisture, debris, and other foreign material; Their mounting or interconnection

Example BTE:

Example ITE:

Example CIC:

Aspects of design and manufacturing of housing parts

Example of design and subsequent manufacture of ear mould:

Example of design of a vent in a hearing aid shell (left-hand figure: general modelling and right-hand figure a method for optimising the shape of the vent)

Electronic adaptation of the hearing aid settings in response to audiological test signals to compensate for hearing aid loss or changes therein, i.e. initial or subsequent fitting.

Initial fitting is generally carried out by an acoustician. Subsequent fitting can be carried out by the acoustician or by the user, e.g. with audiological test signals generated in the hearing aid.

Further detail is covered by Indexing Code subgroups H04R 2225/39, H04R 2225/81 and H04R 2225/83. Classification is obligatory.

Electric tinnitus maskers providing an auditory perception e.g. an acoustic noise signal around the tinnitus frequency. The tinnitus maskers can be stand-alone devices or can be integrated in a hearing aid.

Audio distribution systems for buildings, e.g. stations or religious facilities, for venues, e.g. in stadiums or in concerts halls, or for domestic use, i.e. multiroom.

Public address systems for buildings, e.g. stations or religious facilities, for open air, for indoor and outdoor venues, e.g. in stadiums or in concerts halls, or for domestic use, i.e. multiroom.

Further detail is covered by the subgroups of Indexing Code group H04R 2227/00 and by Indexing Code groups H04R 2420/05 and H04R 2430/03. Classification is obligatory.

Inductive loop or similar systems to enable communication with the hard of hearing.

Further detail is covered by the subgroup of Indexing Code groups H04R 2420/05 and H04R 2430/03. Classification is obligatory.

Loudspeaker 102 the one under test is in the exemplary figures below.

Loudspeaker 108 is the reference loudspeaker.

As an illustrative example:

For example:

Example for test method:

Example for testing arrangement to test a plurality of microphones:

For example:

Functioning of the microphones (102a, 102b) is monitored (error detection 110) and if one microphone is considered defect, its signal is not used for further processing.

For example: US6272229.

For example: microphone matching in a microphone array in general

For example: microphone matching (CABLE) in an adaptive interference canceller (side-lobe canceller):

For example:

In the PA system shown in the figure control device (CD) polls all monitoring devices 12,14 and line monitoring devices 16 to check if errors have occurred: Monitoring 12 checks for example whether the voice coil in the loudspeaker is an open connection (e.g. loudspeaker is defect)

Apparatus or processes specially adapted for the manufacture of

Further detail is covered by Indexing Code groups H04R 2201/003, H04R 2231/001 and H04R 2231/003. Classification is obligatory.

For example: Aluminium diaphragm (1) is pressed (5-7) out of an aluminium plate. The diaphragm is chemically treated cleaned (8-10) and the resulting diaphragm is treated with anodic oxidation to form an amorphous ceramic diaphragm of Al₂O₃. The amorphous diaphragm is heat treated to create corundum, a crystalline form of Al₂O₃.

Further detail is covered by Indexing Code group H04R 2207/021 and the subgroups of H04R 2307/00. Classification is obligatory.

For example: A transducer is assembled with the help of jig 1 and jig 12 used for relative positioning of the parts during assembly. Jig 12 is removed before mounting of bottom frame 8. Jig 1 is removed after complete assembly.

For example: A centre pole cap 88 is formed with cap die press 82. With help of pattern roller 82 an axial griping surface 92 is formed on the centre pole 16, after which the cap is pressed on the pole with press 86. The cap is held in place by interference fit.

For example:

For example: (amplifier (10) mounted to transducer (20))

(amplifier mounted to loudspeaker enclosure)

For example: (the active loudspeaker (311,312) is placed in a separate enclosure (11,12) used in a television)

For example: manufacture of loudspeaker casing with backloaded horn using two lateral plates (1) and a plurality of intermediate plates (2) which are screwed together (6,7).

For example: assembly of loudspeaker.

Typical components are earpiece supports, ear tips, and ear cushions, transducers specially adapted for earphones or headphones.

For example: (monophonic: microphone (40)).

For example: (stereophonic; microphone (30)).

First illustrative example of the subject matter classified in H04R 2201/109: 

Second illustrative example of subject matter classified in H04R 2201/109: 

Third illustrative example of subject matter classified in H04R 2201/109: 

For example:US5933508 (phase plug of a compression driver), US2006153412 (phase plug used with a transducer).

For example: (phase plug (30) of a compression driver)

For example: (phase plug used with a transducer)

See for example: generation of multiple sound channels (12-1, 12-2) to reproduce stereophonic sound

For example: (electric connection)

JP2005136895 (acoustic connection)

For example: (two-channel microphones in earpiece (2a, 2b) mounted on a spherical structure (1) for four-channel sound capture).

For example: (multiple channels (20, 20') in earpiece (30) of headphones).

For example: (multiple channels in single loudspeaker box).

For example: (multiple channels in single loudspeaker box, comprising a pistonic loudspeaker transducer (7) and a distributed mode panel (3) with exciters (5)).

Aspect relating to the relative positioning of loudspeaker enclosures, e.g. determination of their actual position

For example:

For example: (flange (a) to prevent deformation of dome during firing to obtain a ceramic diaphragm

For example: (annular skirt (54) extending from the dome (52), around which a voice coil is wound)

For example: (passive reduction with the help of a weight (23) mounted at the rear side of the magnetic circuit (25) of loudspeaker transducer (25)).

For example (active reduction with the help of a second magnetic circuit (5B). This second magnetic circuit is similar to the first magnetic circuit (5A) driving the diaphragm (8 and attached thereto. Voice coil 7B is driven with part of the signal with which voice coil 7A is driven, such that a weight coupled to the coil 7B move in a direction opposite to that of the diaphragm (8)).

For example: (short circuited moving coil (28) and static driving coil (23)

For example: a flat bi-layer tape (21) extending around a minor axis (24) in a helix to form a helical electro-active structure extending along the minor axis (24). The tape can be used as shown in the right-hand figure to obtain a loudspeaker driver (480).

Construction or application of such transducers. Sound generation may be using piezoelectric, electrostatic, or other principles.

For example: schematic driving circuit (14, 6, 27) for a parametric loudspeaker array comprising a plurality of modules (12, 29).

An example for the modules used with the driving circuit above is shown in the figure directly below. A conductive electrode unit (32), a dielectric spacer (34) provided with an array of apertures (36), and a metallized polymer membrane (38). The components (32-38) are compressed against the spring (30) by an upper ring (40) that bears against the film (38) and threadably engages a base member (42) that supports the spring (30). The module (29) comprises a plurality of electrostatic transducers, corresponding with the respective apertures (36) in the polymer spacer (34).

For example: sound reproduction for a TV, one parametric loudspeaker and one conventional nonparametric loudspeaker per channel.

For example: Rechargeable battery (31) and battery charger 5 with charging contacts (51, 51')

For example: Fuel cell (6) with fuel cell tank (8). Valve (9) is used for filling the tank and with the help of window (10) the amount of fuel can be checked.

For example: Thermic semiconductor elements (2) arranged on the outer surface of hearing aid.

For example: A hearing aid comprises a step-down/step-up converter (3) as voltage regulator, which transforms both higher as well as lower operating voltage into at least one stabilised supply voltage.

For example: Power source (206) is connected to a charge pump and voltage regulator (208), which generates a larger or smaller output voltage depending on the value of the power source (206) and stabilises the output voltage.

For example: Hearing aid with data logger (60) which logs data relating to sound environment, programs used, etc. The data stored can be used by subsequent fitting.

For example: Acoustic scene identification method for hearing device, which involves extracting characteristic feature of input signal and generating revised class information in processing stages to characterize and identify acoustic scenes. The settings can be adapted to the encountered acoustic scene, if its characteristics are detected.

Application of speech processing techniques, e.g. formant processing, determination or use of speech intelligibility threshold, detection of voiced speech, to control a hearing aid to enhance speech intelligibility.

The mere mentioning of increasing speech intelligibility, which is a general aim for hearing aids, should not be classified.

For example: Passive shielding of a microphone transducer (21) by metal jacket (30)

For example: Active shielding by attenuation loops (8, 9) to attenuate electromagnetic interference resulting from supply lines (6C, 6D, coming from battery (6)) or the amplifier (3) and receiver (4) at the site of antenna (7)

For example: Compensation for em-noise in signal processing:

A hearing aid receives the electromagnetic disturbance signal (14) via the detector element (12) and therefore detects the presence of, for example, a GSM telephone in the D1 network. The detector element (12) transmits the information about the detected noise field type (namely GSM telephone, D1 network) to the DSP element (3), so that the filter element (13) can be configured in a way that is adapted to the detected noise field type for the particularly effective noise field suppression.).

For example: Construction of the antenna

For example: Circuitry for transmitting signal between hearing aid (2) and an external device (1):

For example: Sound delivered to the deaf ear (18) is sent to the other ear (19) and processed to maintain some directional hearing.

If the other ear is also impaired it is called Bi-CROS.

For example:

For example: multiple amplifiers to one single receivers

For example: multiple amplifiers to multiple receivers, with same or different characteristics

For example:

Implantable hearing aids or parts thereof, e.g. receivers, housings, whereas in H04R 25/606 the emphasis is on the mounting of the transducers.

For example:

For example: The ohmic resistance of the skin is measured. Under stress the ohmic resistance reduces due to sweating. Thus this resistance can be taken as a measure of psychoacoustic variables, e.g. loudness, sharpness, audio stress, etc.

For example: compensation for the change in characteristics of a child's ear during growth

Adaptation of the signal processing is generally done by sensing the interference signal or noise. For example: A PA system has two audio inputs (6, 7) provided for interference signal and a utility signal, respectively. An adjustment device (11) adjusts the utility signal with the interference signal in such manner that a modified utility signal is produced. An audio output is provided for the modified utility signal. The interference signal contains information about local distribution of static noises.

For example:

For example:

For example: reverberation adaptation for indoor or outdoor venues for PA-systems.

For example: Amplifiers (312) have the amplification gain, which is the function of the bandwidth (308) of the filter (306), thus effectively augmenting the speech in noisy conditions, and hence preserving the overall sound pressure level and increasing speech intelligibility. The appropriate amplifier/filter combination is selected by a switch (304), which can be manually or automatically controlled by a switch controller (316) (cf. figure).

For example: A method involves sensing the ambient sound in a region for a predetermined time interval, analyzing sensed ambient sound and overlaying ambient sound with test audio signals having predetermined characteristics. The overlaid ambient sound is sensed. The degradation of speech intelligibility beyond acceptable level is determined by analyzing ambient sound pressure level and ambient frequency domain characteristics (cf. figure).