Abstract: A balanced receiver providing significantly reduced vibration is disclosed. The balanced receiver comprises a closed loop operably attached between an armature and a diaphragm. The effective moving mass of the diaphragm is designed to match the effective moving mass of the armature. The closed loop facilitates the balancing of the motion of the diaphragm and the motion of the armature, thus reducing the vibration of the receiver.

Abstract: A system and method for assisting listening wherein an integrated circuit selects one or more audio sources from among a plurality audio sources to be presented to a signal processing circuit. Selection of the audio source can be automatically executed in response to detection of an external magnetic field, such as from a telephone handset, or manually controlled by a user input.

Abstract: A system and method for assisting listening wherein an integrated circuit selects one or more audio sources from among a plurality audio sources to be presented to a signal processing circuit. Selection of the audio source can be automatically executed in response to detection of an external magnetic field, such as from a telephone handset, or manually controlled by a user input.

Abstract: A directional microphone system is disclosed, which comprises circuitry for low pass filtering a first order signal, and circuitry for high pass filtering a second order signal. The system further comprises circuitry for summing the low pass filtered first order signal and the high pass filtered second order signal. A method of determining whether a plurality of microphones have sufficiently matched frequency response characteristics to be used in a multi-order directional microphone array is also disclosed. For a microphone array having at least three microphones, wherein one of the microphones is disposed between the other of the microphones, a method of determining the arrangement of the microphones kin the array is also disclosed.

Abstract: An acoustical switch is provided for a directional microphone of a hearing aid device. The hearing aid device includes a faceplate having a switch aperture, a front port, and a rear port. The microphone includes a front inlet in communication with the front port within the face plate and a front chamber of the microphone. The microphone further includes two rear inlets in communication with the rear port within the faceplate and a rear chamber of the microphone. The acoustical switch comprises a switch actuator having a body portion and a lever portion. The body portion includes a first closure surface and a second closure surface. The switch actuator is adapted to be disposed within the switch aperture of the face plate of the hearing aid device such that the body portion is disposed adjacent to the inlets of the microphone.

Abstract: An electret condenser microphone includes a housing, a diaphragm disposed within the housing, first and second sound inlet ports and an acoustic resistive material disposed within the housing and in the acoustic path between the second inlet port and the diaphragm. The acoustic resistive may further electrically couple a backplate coupled to the diaphragm to an amplifier disposed within the housing.

Abstract: A transducer assembly may include a first transducer having a first front volume, a first back volume and a first port acoustically coupled to the first front volume; and a second transducer having a second front volume, a second back volume and second port acoustically coupled to the second front volume. The first front volume and the second front volume are acoustically coupled to increase the effective back volume of both the first transducer and the second transducer. An optional signal processing circuit may be used to control the output of the first transducer based upon a signal received from the second transducer.

Abstract: A silicon condenser microphone is described. The silicon condenser microphone of the present invention comprises a perforated backplate comprising a portion of a single crystal silicon substrate, a support structure formed on the single crystal silicon substrate, and a floating silicon diaphragm supported at its edge by the support structure and lying parallel to the perforated backplate and separated from the perforated backplate by an air gap.

Abstract: A microphone includes a housing, an acoustic port formed in the housing, a diaphragm disposed within the housing adjacent the acoustic port, a backplate assembly operably disposed within the housing in spaced relationship relative to the diaphragm and a circuit assembly disposed within the housing. A connecting member extends between the circuit assembly and the backplate assembly to secure mechanically the backplate assembly within the housing and to couple electrically the backplate assembly to the circuit assembly.

Abstract: A transducer assembly includes at least one transducer. The transducer is disposed within a holder assembly. In this regard, the holder assembly is formed to have an interior and an exterior with the interior having a size to receive and retain the transducer. The exterior of the holder assembly is configured to be received and retained within a recess of a device.

Abstract: A method of making an acoustic assembly for use in a transducer includes forming a multi-layer structure. The multi-layer structure includes a first layer member that includes a first center portion, a first edge portion and a first aperture separating the first center portion and the first edge portion. A second layer member includes a second center portion, a second edge portion and a second aperture separating the second center portion and the second edge portion such that the second center portion is free to move relative to the second edge portion. The first and second layers are formed into an assembly wherein the first center portion and the second center portion are coupled, the first edge portion and the second edge portion are coupled, and the first aperture and the second aperture are substantially aligned to define a passageway. The assembly has an assembly stiffness that is greater than the stiffness of either the first or second layer members.

Abstract: An acoustic assembly for use in a transducer includes a multi-layer structure. A first layer member includes a first center portion, a first edge portion and a first aperture separating the first center portion and the first edge portion. A second layer member includes a second center portion, a second edge portion and a second aperture separating the second center portion and the second edge portion such that the second center portion is free to move relative to the second edge portion. The first and second layers are formed into an assembly wherein the first center portion and the second center portion are coupled, the first edge portion and the second edge portion are coupled, and the first aperture and the second aperture are substantially aligned to define a passageway. The assembly has an assembly stiffness that is greater than the stiffness of either the first or second layer members.

Abstract: An apparatus is provided for matching the response of a pair of microphones. The two microphones provide a first and second output, respectively, in response to an audible input. The microphone outputs are subtract from each other to produce a gain control output for operably controlling the gain of the first microphone output, resulting in a gain compensated microphone output. A phase adjustment circuit also is provided responsive to the gain compensated microphone output and a rolloff control output for producing a matching output. The rolloff control output is generated by a phase difference subtractor circuit responsive to both the matching output and the second microphone output. Moreover, the output of at least one of the microphones has a resonance frequency that is shifted to a desired preselected frequency.

Abstract: A receiver, such as for use in a hearing aid, is disclosed. The receiver comprises a housing and a diaphragm assembly disposed within the housing. The diaphragm assembly acoustically divides the housing into a front volume and a back volume. The diaphragm assembly comprises a paddle having a perimeter, a flexible annulus connected to the paddle, and a diaphragm support, wherein the diaphragm support secures the perimeter of the annulus to the housing. The receiver further comprises a plurality of apertures in the diaphragm assembly, wherein the plurality of apertures provides an acoustic distortion of no greater than 2% THD.

Abstract: A method and apparatus for substantially reducing and virtually eliminating direct current flow through the input transistor(s) of an input buffer circuit for an electret microphone is disclosed. An input transistor is provided and operably connected to an input and an output of the input buffer circuit. The input transistor has a first operating state wherein current flow occurs in a first direction and a second operating state wherein the a current flow occurs in a second direction—opposite that of the first direction. The input transistor is biased to alternately control operation between the first operating state and the second operating state. The alternating, opposing flows of current of the respective operating states cooperate to substantially reduce and virtually eliminate the flow of direct current through the input transistor(s) of the buffer circuit.

Abstract: A silicon condenser microphone package includes a transducer unit, a substrate, and a cover. The substrate includes an upper surface transducer unit is attached to the upper surface of the substrate and overlaps at least a portion of the recess wherein a back volume of the transducer unit is formed between the transducer unit and the substrate. The cover is placed over the transducer unit and either the cover or the substrate includes an aperture.

Abstract: A module (100, 200, 300, 400, 500, 600, 900) may be electrically connected to a PCB (18, 918) residing in a device (14) or may be joined to the device (14) to form a portion of the housing (16, 916) of the device (14). The module may include a housing (102, 202, 302, 402, 502, 602) having at least one layer, a surface mountable component, such as a surface mountable acoustic transducer (110, 210, 310, 410, 510, 610, 910) having a connecting surface (114, 214, 314, 414, 514, 614, 914), and at least one acoustic port (124, 224, 324, 424, 524, 624, 924) to couple a surface of the surface mountable acoustic transducer to the exterior of the device (14). The module (100, 200, 300, 400, 500, 600, 900) may further include a secondary mounting structure (654) electrically connected to the connecting surface (114, 214, 314, 414, 514, 614, 914) of the surface mountable acoustic transducer (110, 210, 310, 410, 510, 610, 910).

Abstract: The disclosure relates to electroacoustic receivers of the type which incorporate a reed armature. Thus, a receiver comprises a coil, magnets, pole pieces and a reed armature which passes through a central tunnel defined by the coil. A central portion of the reed lies within the tunnel. The coil includes a predetermined winding for decreasing the parasitic capacitance of the coil.

Abstract: Various linkage assemblies are shown and described for connecting a first movable member to a second movable member of a transducer. The linkage assemblies provide for motion amplification or reduction and, when used for sound generating purposes such as hearing aids or speakers, three different schemes for compensating for amplification-induced distortion. One scheme for compensating for distortion while providing amplification is the use of a lower horizontal span segment in a closed-loop linkage assembly that is longer than a corresponding upper horizontal span segment or upper vertex. Thus, a horizontal span segment used to connect the loop to the first movable member of the armature is longer than a corresponding segment or vertex used to connect the loop to the second movable member. A second distortion compensating feature that provides amplification is found in the use of non-parallel legs used to connect the linkage loop to the housing.

Abstract: A solid-state transducer is disclosed. The transducer comprises a semi-conductor substrate forming a support structure and having an opening. A thin-film structure forming a diaphragm responsive to fluid-transmitted acoustic pressure is disposed over the opening. The transducer further includes a plurality of semi-conductor supports and tangential arms extending from the diaphragm edge for connecting the periphery of the diaphragm to the supports. The tangential arms permit the diaphragm to rotate relative to the supports to relieve film stress in the diaphragm. The transducer still further includes a plurality of stop bumps disposed between the substrate and the diaphragm. The stop bumps determine the separation of the diaphragm from the substrate when the transducer is biased.