Abstract: This invention provides methods and apparatus for focusing a hypersonic beam to control both a direction and depth of audible information delivery. Signals that are delivered to each of a plurality of hypersonic transducer elements are adjusted in phase so that transmitted hypersonic signals are focused at a focal point anywhere in space. The focal point of a focused hypersonic beam may be used to scan a space of interest when used in a receive mode in a pinging process. When objects are detected, a focused hypersonic beam may be used to deliver audible information substantially only to a neighborhood of the detected object.

Abstract: The present invention relates to systems and methods for protecting acoustic devices. In particular embodiments, barriers are useful for preventing a variety of solid, liquid, and vapor contaminants from modifiying or damaging the performance of acoustic transducers, while at the same time providing essentially an acoustically transparent passage of sound.

Abstract: Improved approaches to flexibly implementing graphic equalizers on media players are disclosed. These approaches provide dynamic order reduction of a multi-band graphic equalizer so that equalizer effects can be timely performed with only limited computational resources. In one embodiment, a media player receives a media item and associated equalizer settings for a multi-band graphic equalizer. The media player can then automatically (i.e., without user action) approximate the multi-band graphic equalizer with the equalizer settings for the media item using a fewer number of filters. Fewer filters means order reduction, and thus reduction in computational requirements. After the multi-band graphic equalizer is approximated, the media player can present the media item to its user in accordance with the reduced complexity, approximated equalizer.

Abstract: A noise estimation unit estimates a noise signal in an input signal. A section decision unit distinguishes a target signal section from a noise signal section in the input signal. A noise suppression unit suppresses the noise signal based on a first suppression coefficient from the input signal. A noise excess suppression unit suppresses the noise signal based on a second suppression coefficient from the input signal. The second suppression coefficient is larger than the first suppression coefficient. A switching unit switches between an output signal from the noise suppression unit and an output signal from the noise excess suppression unit based on a decision result of the section decision unit.

Abstract: Provided are a three-dimensional audio signal processing system using a rigid sphere and a method thereof. The three-dimensional audio signal processing system of the present research simplifies the shape of a human head into a rigid sphere, acquires three-dimensional audio signals by setting up mikes on the rigid sphere, and applies the acquire three-dimensional audio signals to diverse existing reproduction systems. The system includes a three-dimensional audio signal acquiring unit for acquiring audio signals by using a predetermined number of mikes set up on the rigid sphere; and a three-dimensional audio signal post-processing unit for converting the acquired audio signals to reproduce in diverse reproduction environments such as five-channel, four-channel, headphone, stereo, and stereo dipole reproduction environments.

Abstract: Methods and apparatus for enabling auto-recovery of a digital audio amplifier after a short-circuit are disclosed. In accordance with one embodiment, a short-circuit is detected by both detecting a switching signal at an output of the digital audio amplifier and sensing a mute signal coupled to the digital audio amplifier. Once a short-circuit has been detected, a reset signal is provided to a reset input of the digital audio amplifier when the switching signal indicates that the digital audio amplifier is not switching and the mute signal indicates that the amplifier is in an un-muted state.

Abstract: A method of designing a beamformer, and a beamformer made in accordance with this method, characterized by a uniform speakerphone response condition, resulting in optimal beamforming directivity under a uniform coupling constraint. According to the present invention, a finite number of individual beamformers are constrained to have the same response to a loudspeaker signal (as well as the same gain in their respective look directions) without specifying the exact value of their response to this signal. This results in beamformer weights that are optimal in the minimum variance sense and satisfy the uniform coupling constraint. The minimum variance condition combines all beamformer weights at once, and the uniform coupling constraint is expressed as a finite number of linear constraints on the weights of the individual beamformers, without specifying an arbitrary, a priori value for the actual value of the uniform response.

Abstract: A method is provided for discriminating between the case of a single talker with an acoustic reflection and the case of two talkers, regardless of their power levels. The method is implemented in real time by performing a cross-correlation between pairs of average power signals originating from pairs of beamformers. A detection decision is then made based on the value of the cross correlation and its lag.

Abstract: An active vibratory noise control apparatus reduces vibratory noise which is produced in the passenger compartment of a vehicle based on vibratory noise generated by a variable-cylinder internal combustion engine that can selectively be operated in a full-cylinder operation mode in which all of the cylinders are operated and a partial-cylinder operation mode in which some of the cylinders are out of operation. The active vibratory noise control apparatus has a partial-cylinder operation mode determining circuit for determining whether the variable-cylinder internal combustion engine is in the partial-cylinder operation mode or not. Depending on a determined result from the partial-cylinder operation mode determining circuit, a transistor is turned on or off to switch an amplifying circuit which drives a speaker into and out of operation.

Abstract: A speaker system includes a first, second and third sound radiators with the second sound radiator positioned medially between the first and third sound radiators. The radiators project first, second and third sound vectors respectively, with the second sound vector oriented vertically and the first and third sound vectors directed generally toward each other at angles above the horizontal so as to intersect at an inclusive angle between 90 and 170 degrees. Sound from the first and third radiators impinges on the second radiator so as to cause an echo effect improving sound spaciousness. The first and third radiators are placed at different angles relative to the listener and at different heights as well to improve time delays in the two radiated signals.

Abstract: A method and apparatus determine a channel response for an alternative sensor using an alternative sensor signal and an air conduction microphone signal. The channel response is then used to estimate a clean speech value using at least a portion of the alternative sensor signal.

Abstract: An audio system, an audio apparatus, and a method for performing audio signal output processing are provided that prevent the occurrence of sound interruption of high-priority voice signal output, such as voice guidance for navigation. The audio system includes the audio apparatus communicatively connected to an electronic device for producing an audio signal and to an electronic device for producing a high-priority voice signal (voice guidance signal). When the voice guidance signal is received with the audio signal being received, the audio apparatus starts to perform a mixing operation of the voice guidance signal. If a request for switching a sample rate of the audio signal is made during the mixing operation, the audio apparatus suspends a sample-rate switching operation until the mixing operation is completed.

Abstract: A sound system for industrial tool chests modifies a tool chest with drawers to provide sound and music to technicians at work in a shop. The sound system has a power supply and electronics mounted in the vacant spaces within a tool chest. The power supply has ducting and a fan for cooling. Wiring delivers power from the power supply to the electronics and a player. The electronics include a dropping resistor and illuminated on-off switch. The player can play one or all of AM, FM, and other radio bands, broadcast or cable TV, video and other digital signals, and recorded media of many kinds. The player distributes a signal to two or more speakers mounted to the bottom of the tool chest, and alternatively in the top. The present invention installs within single chests and multiple story chests. Sound from the speakers reflects upon a shop floor to send music throughout the shop.

Abstract: Microphone equalization is implemented in a directional microphone system of the second or a higher order with at least three omnidirectional microphones. Initially, the signal levels of the microphone signals generated by the three omnidirectional microphones are compensated. The phase is subsequently varied in one of the three microphone signals until the signal levels of the directional microphones of the first order that are formed from the three omnidirectional microphones, are also compensated.