Abstract: A sound system and a method for noise cancellation in a room is provided, the method comprising arranging a set of microphones at a distance from an opening in a wall of the room for provision of one or more microphone input signals including a first microphone input signal; arranging a set of speakers in a vicinity of the opening; determining, based on at least the first microphone input signal, one or more output signals for the set of speakers for matching of sound entering the room through the opening; generating the one or more output signals; and outputting sound signals based on the one or more output signals with the set of speakers.

Abstract: A force feedback actuator includes a pair of electrodes and a dielectric member. The pair of electrodes are spaced apart from one another to form a gap. The dielectric member is disposed at least partially within the gap. The dielectric member includes a first portion having a first permittivity and a second portion having a second permittivity that is different from the first permittivity. The dielectric member and the pair of electrodes are configured for movement relative to each other.

Abstract: A force feedback actuator includes a pair of electrodes and a dielectric member. The pair of electrodes are spaced apart from one another to form a gap. The dielectric member is disposed at least partially within the gap. The dielectric member includes a first portion having a first permittivity and a second portion having a second permittivity that is different from the first permittivity. The dielectric member and the pair of electrodes are configured for movement relative to each other.

Abstract: An example apparatus comprises a drive coil energizable by a drive signal, at least one permanent magnet, and at least one magnetic return path element for flux induced by the drive signal, the magnetic return path element, such as a balanced armature, being configured to provide a variable reluctance, so as to reduce nonlinearities in a displacement versus drive signal relationship. Modifying the reluctance versus flux properties of the magnetic return path of a transducer, e.g. the armature of a balanced armature device, allows compensation for nonlinearity arising in another part of the apparatus.

Abstract: An example apparatus comprises a drive coil energizable by a drive signal, at least one permanent magnet and at least one magnetic return path element for flux induced by the drive signal, the magnetic return path element, such as a balanced armature, being configured to provide a variable reluctance, so as to reduce nonlinearities in a displacement versus drive signal relationship. Modifying the reluctance versus flux properties of the magnetic return path of a transducer, e.g. the armature of a balanced armature device, allows compensation for nonlinearity arising in another part of the apparatus.

Abstract: A receiver assembly includes a first diaphragm assembly having a diaphragm, and a second diaphragm assembly having a diaphragm. A linkage assembly is coupled to an armature of the receiver. The linkage assembly is also coupled to the first diaphragm assembly and to the second diaphragm assembly.

Abstract: A receiver assembly includes a housing having a fixed housing portion and a shiftable housing portion cooperating to define a hollow cavity. A flexible membrane secured between the fixed housing portion and the shiftable housing portion and adapted to allow relative motion between the fixed and shiftable housing portions. The receiver assembly further includes a magnetic motor assembly including a displaceable drive rod; and a link assembly having a first end fixedly attached to an inner surface of the shiftable housing and a second end coupled to the drive rod. The link assembly translates the shiftable housing portion relative to the fixed housing portion in response to the displacement of the drive rod.

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 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 in the array is also disclosed.

Abstract: A receiver assembly includes a housing having a fixed housing portion and a shiftable housing portion cooperating to define a hollow cavity. A flexible membrane secured between the fixed housing portion and the shiftable housing portion and adapted to allow relative motion between the fixed and shfitable housing portions. The receiver assembly further includes a magnetic motor assembly including a displaceable drive rod; and a link assembly having a first end fixedly attached to an inner surface of the shiftable housing and a second end coupled to the drive rod. The link assembly translates the shiftable housing portion relative to the fixed housing portion in response to the displacement of the drive rod.

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: 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 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 in the array is also disclosed.

Abstract: A direction selective transducer which includes a center mass fixed between two active transducer element stacks and two head masses. The center mass couples the two stacks and allows the ratio of radiation produced by each head mass to be selected as desired by varying the amplitude and phase of drive voltages applied to the stacks. The transducer can also be used as a directional receiver.

Abstract: A broadband longitudinal vibrator transducer having a laminar head mass section including at least three layers coupled to electromechanical transducer elements. The head section includes a forward head mass, a compliant member abutting the forward head mass and a rear head mass abutting both the compliant member and the transducer elements. The compliant member allows the head mass section to mechanically resonate in at least two frequencies expanding the bandwidth of the transducer. The compliant member can be an active transducer element.

Abstract: A broadband radial vibrator transducer having at least two laminar resonant sections coupled to a radial electromechanical transducer element where each laminar section includes at least two layers. Each resonant section has a mass layer and a compliant member layer where the compliant member layer is fixed between the transducer element and the mass layer. The compliant member allows the resonant section to mechanically resonate along with the transducer element providing at least two resonant frequencies, thereby expanding the bandwidth of the transducer.