Abstract: A 3D sound reproducing apparatus for multiple listeners includes an inverse filter module for filtering an input sound signal such that each of the listeners can have the same virtual sound source, time multiplexing module for sequentially selecting one of the sound signals filtered by the inverse filter module at a predetermined interval, and a plurality of speakers for outputting the sound signal selected by the time multiplexing means as sound. Thus, the 3D sound reproducing apparatus for multiple listeners can concurrently present the same 3D sound effect to multiple listeners.

Abstract: In a method for determining a parameter set for a hearing aid during the computerized setting of the hearing aid, a macro call is determined, the macro call is converted into at least one setting command according to a macro definition, and the parameter set is determined dependent on the at least one setting command. Such a method is high-performance and nonetheless flexible and easy to manipulate.

Abstract: A portable spa including an audio system designed to use the spa shell as the sound generating device. Transducer devices are mounted within an enclosure which is bonded to the spa shell so as couple the sound vibration energy to the shell so that sound can be heard when using the spa.

Abstract: A combined conversation mirror and intercom is mounted in a mirror frame pivotally mounted to a vehicle accessory, such as an overhead console. The frame is movable between an unobtrusive stored position and an extended use position located such that the vehicle operator can see mid or rear seat passengers, and, similarly, the mid or rear seat passengers can see the vehicle operator. In a preferred embodiment of the invention, an electrical switch is coupled between the mirror frame and vehicle accessory such that movement of the mirror frame actuates the switch for powering the intercom circuit.

Abstract: In a method and apparatus for producing constant sound pressure level in a hearing aid, a microphone, a receiver and a signal processing unit are provided. A switching unit produces constant sound pressure levels. The switching unit has an envelope generator for producing an envelope value of a signal value to be processed and a divider for calculating the ratio of the signal value and the envelope value as the signal to be output or further processed.

Abstract: In a method of processing an input signal, the input signal is divided into a plurality of subbands with the aid of bank of complex valued, single-sided subband filters. The single-sided frequency spectra of the resulting subbands make aliasing negligible at near twice the critical downsampling rates.

Abstract: According to the present disclosure, a digital vehicle microphone system for recording and playback of announcements pertaining to vehicle stops and route information is provided for use over public address systems installed on public transportation vehicles. The system includes a microphone apparatus for digitally pre-recording the announcements. The microphone apparatus includes a microphone, a mute switch, a radio mode switch, a record switch and a record indicator. The system also includes a control circuit for recording and storing at least two separate announcements onto memory storage devices. The control circuit further includes a delayed playback feature for delayed playback of the announcements through the vehicle's public address system. The microphone apparatus further includes a “hands free” microphone including hand and foot actuated recording switches.

Abstract: A portable spa including an audio system designed to use the spa shell as the sound generating device. Transducer devices are mounted within an enclosure which is bonded to the spa shell so as to couple the sound vibration energy to the shell so that sound can be heard when using the spa.

Abstract: Apparatus for reducing noise emitted from an appliance having a cabinet that supports at least one component that emits at least one acoustic pressure wave therefrom. In a preferred form, the apparatus comprises at least one diffuser having at least one deflection surface. The diffuser is coupled to the cabinet and positioned relative to the one component such that the acoustic pressure wave emitted from the component is deflected by the one deflection surface in a predetermined direction. The diffuser can be used to deflect acoustic pressure waves such that they collide with each other. The apparatus may further include at least one absorber. The diffuser is strategically located to deflect acoustic pressure waves being emitted from the component into the absorber to reduce the noise emitted from the appliance.

Abstract: The present invention is an amplifier signal distribution module ideally suited for use in public announcement systems, concerts, and live sound reinforcement. This present invention will be used with conventional components of an audio system. In use, the present invention will receive a combined signal from a signal processor and transmit the signal to a cross-over. The cross-over will transmit the signal to amplifiers which will send the signal back to the present invention. The signal is re-distributed to a final output source, such as speakers. Each input, output, and input/out sections of the present invention includes various sets of connectors for accepting any conventional form used with the conventional components. Such an arrangement will drastically reduce the time and cabling generally associated in the process of setting up audio system for live audio performance.

Abstract: Distortion modeling produces distortion models for use by a distortion synthesizer to synthesize the harmonic distortion effects of audio distortion devices. A sinusoidal waveform is distorted by an audio distortion device and analyzed using a Fourier transform to produce a distortion model comprising harmonic amplitude and phase parameters. A phase correction process compensates for phase shifts induced by the audio distortion device. The distortion synthesizer uses a distortion function that distorts a digital audio signal according to the distortion model. The distortion model can be modified to alter the distortion effect and can be stored in a data-storage device for later retrieval. A frequency bandsplitter and signal mixer allow the distortion effect to be applied only to the low frequency content of the digital audio signal, thus providing spectral headroom to suppress the production of aliasing noise.

Abstract: A method and system for selectively and variably attenuating audio data are disclosed. A high-volume control value as selected by a user is first received, and this high-volume control value defines a volume output level for high amplitude audio samples. An attenuation factor is then determined by utilizing the high-volume control value. Each sample from an incoming audio data stream is conditionally attenuated with the attenuation factor such that high amplitude audio data get compressed while low amplitude audio data remain unaffected. Finally, the attenuated samples are sent to an output.

Abstract: A multi-channel stereo converter is described comprising stereo magnitude determining means for generating a stereo information signal (a/b; &rgr;), which represents a degree of stereo between audio input signals (L, R), and transforming means for transforming said audio signals (L, R) based on said stereo information signal (a/b; &rgr;) into at least a surround signal (S). A space mapping interpretation is presented and an audio center signal may be derived from the stereo input signals as well. The result is more flexibility in application and design, without substantial cross talk in the audio signals.

Abstract: An adaptive system and method for reducing interference in a signal received from an array of sensors. Adaptive filters are used to generate cancelling signals that closely approximate the interference present in the received signal. The adaptive filter weights are converted into the frequency domain where the frequency representation values in a selected frequency range are truncated to avoid signal leakage involving narrow band signals. Deodorizing filters are used to produce the cancelling signals having a flat frequency spectrum. Normalized power difference is used limit the operation of the adaptive filters to the case where there is some directional interference to be eliminated.

Abstract: An audio system, in particular for motor vehicles, having a loudspeaker installation for supplying sound to an audio chamber and a control unit with a signal detection unit for receiving microphone signals from at least one microphone exposed to the audio chamber outputting the signal to an evaluation unit which extracts interference signals from the microphone signals. The control unit produces control signals on the basis of these interference signals in order to operate the loudspeaker installation. To reduce the complexity for installation of such an audio system, at least one tweeter is connected in the loudspeaker installation as a microphone.

Abstract: An acoustic conditioning apparatus. The mechanism includes an attenuator to limit excessive noise levels. The attenuator includes a circuit for compressing an output sound pressure level below a desired level, such as 90 dBA over an eight-hour period. The mechanism also includes an amplifier for conditioning ambient sound level in accordance with the normal needs of a hearing impaired person using the conditioning apparatus. Additionally included is a switch in an electrical circuit to enable selection of attenuation of excessive noise levels or normal amplification. The switch can be controlled either manually by means of a toggle on a housing enclosing the various components, or automatically in response to the sensed noise level.

Abstract: This is a design for a microphone which directly outputs a one-bit digital audio signal. No electronic analogue-to-digital converter is required.

Abstract: A sound processing circuit for distributing low frequency signal components of multichannel audio signals. The sound processing circuit filters low frequency signal components from the digital audio signals of m (m≦n) specified channels using an exclusive channel having low frequency signals and n (n>1) multiple independent channels, and outputs the filtered low frequency signal components as part of a low frequency signal channel.