Abstract: A method for adjusting the clarity of an audio output in a changing environment, including: receiving a content signal; applying a customized gain to the content signal; and outputting the content signal with the customized gain to at least one speaker for transduction to an acoustic signal, wherein the customized gain is applied on a per frequency bin basis such that frequencies of a lesser magnitude are enhanced with respect to frequencies of a greater magnitude and an intelligibility of the acoustic signal is set approximately at a desired level, wherein the customized gain is determined according to at least one of a gain applied to the content signal, a bandwidth of the content signal, and a content type encoded by the content signal.

Abstract: A noise reduction system includes sensors configured to generate an input signal, an adaptive filter configured to represent a transfer function of a path traversed by the input signal, one or more processing devices, and one or more transducers. The processing devices receive the input signal and generate an updated set of filter coefficients of the adaptive filter by separating the input signal into frequency subbands; determining for each subband, coefficients of a corresponding subband adaptive module; and combining the coefficients of multiple subband adaptive modules. Determining the coefficients of the corresponding subband adaptive module includes selecting a subset of a precomputed set of filter coefficients of the adaptive filter. The processing devices process a portion of the input signal using the updated set of filter coefficients of the adaptive filter to generate an output that destructively interferes with another signal traversing the path represented by the transfer function.

Abstract: A method for adjusting the clarity of an audio output in a changing environment, including: receiving a content signal; applying a customized gain to the content signal; and outputting the content signal with the customized gain to at least one speaker for transduction to an acoustic signal, wherein the customized gain is applied on a per frequency bin basis such that frequencies of a lesser magnitude are enhanced with respect to frequencies of a greater magnitude and an intelligibility of the acoustic signal is set approximately at a desired level, wherein the customized gain is determined according to at least one of a gain applied to the content signal, a bandwidth of the content signal, and a content type encoded by the content signal.

Abstract: An acoustic device includes at least one acoustic transducer disposed such that, in a head-worn state, the at least one acoustic transducer is in an open-ear configuration in which an ear canal of a user of the acoustic device is unobstructed. The acoustic device also includes an array of two or more first microphones that captures audio preferentially from a first direction as compared to at least a second direction different from the first direction, wherein the audio captured using the array is processed and played back through the at least one acoustic transducer, and an active noise reduction (ANR) engine that includes one or more processing devices. The ANR engine is configured to generate a driver signal for the at least one acoustic transducer, the driver signal having phases that reduce effects of audio captured from at least the second direction.

Abstract: Audio systems, methods, and computer readable mediums having program code to receive a harmonic signal related to rotating equipment, such as a vehicle drivetrain in some examples, and provide a harmonic cancellation (or enhancement) signal. The harmonic cancellation signal is transduced into an acoustic signal, and a feedback sensor, such as a microphone, detects an error signal representative of acoustic energy at a first location in the environment. A projection filter filters the error signal to provide an estimated error signal at a second location in the environment, such as at the location of an occupant's ear(s). An adaptive module adjusts the cancellation signal based on the estimated error signal.

Abstract: An acoustic device includes at least one acoustic transducer disposed such that, in a head-worn state, the at least one acoustic transducer is in an open-ear configuration in which an ear canal of a user of the acoustic device is unobstructed. The acoustic device also includes an array of two or more first microphones that captures audio preferentially from a first direction as compared to at least a second direction different from the first direction, wherein the audio captured using the array is processed and played back through the at least one acoustic transducer, and an active noise reduction (ANR) engine that includes one or more processing devices. The ANR engine is configured to generate a driver signal for the at least one acoustic transducer, the driver signal having phases that reduce effects of audio captured from at least the second direction.

Abstract: A method includes receiving multiple samples of time-domain data that includes noise, computing a first two-dimensional (2D) time-frequency representation of the time domain data, and processing the first time-frequency representation using a time-frequency noise reduction mask to generate a second, noise-reduced time-frequency representation of the time domain data. The method also includes generating a time domain output based on the noise-reduced time-frequency representation.

Abstract: An acoustic device includes at least one acoustic transducer disposed such that, in a head-worn state, the at least one acoustic transducer is in an open-ear configuration in which an ear canal of a user of the acoustic device is unobstructed. The acoustic device also includes an array of two or more first microphones that captures audio preferentially from a first direction as compared to at least a second direction different from the first direction, wherein the audio captured using the array is processed and played back through the at least one acoustic transducer, and an active noise reduction (ANR) engine that includes one or more processing devices. The ANR engine is configured to generate a driver signal for the at least one acoustic transducer, the driver signal having phases that reduce effects of audio captured from at least the second direction.

Abstract: An input signal representative of an undesired acoustic noise in a region is captured by one or more first sensors and processed to generate a cancellation signal. An output signal is generated based on the cancelation signal to cause one or more acoustic transducers to cancel, at least in part, the undesired acoustic noise in the region. A feedback signal representative of residual acoustic noise in the region is captured by one or more second sensors. A characteristic of each of the feedback signal, the cancellation signal, and a combination of the cancellation signal and the feedback signal is determined. One or more thresholds are compared to a ratio of (i) the characteristic of the combination of the cancellation signal and the feedback signal and (ii) a combination of the characteristic of the feedback signal and the characteristic of the cancellation signal to determine a convergence state.

Abstract: A noise-cancellation system with secondary path adaptation, includes: a noise-cancellation filter configured to receive a reference signal representative of a source of noise within a predefined volume and generating, based at least in part on the reference signal, a noise-cancellation signal that, when transduced by a speaker, produces a noise-cancellation acoustic signal that reduces noise in a cancellation zone within the predefined volume; a secondary path estimation filter configured to receive an input signal and to implement an estimate of secondary path transfer function, the secondary path transfer function being a transfer function between the speaker and a cancellation zone, the secondary path estimation filter outputting an output signal based, at least in part, on the estimate of the secondary path transfer function and the input signal; an adaptive module configured to adjust coefficients of the noise-cancellation filter according to a first adaptive algorithm, based, at least in part, on the es

Abstract: A method includes receiving multiple samples of time-domain data that includes noise, computing a first two-dimensional (2D) time-frequency representation of the time domain data, and processing the first time-frequency representation using a time-frequency noise reduction mask to generate a second, noise-reduced time-frequency representation of the time domain data. The method also includes generating a time domain output based on the noise-reduced time-frequency representation.

Abstract: An audio system, including an accelerometer positioned to produce an accelerometer signal representative of road noise within a vehicle cabin; a microphone disposed within the vehicle cabin such that the microphone receives the road noise and produces a microphone signal having a road-noise component; and a road-noise canceler, comprising a road-noise cancellation filter, configured to receive the accelerometer signal and the microphone signal and to minimize the road-noise component of the microphone signal according to the accelerometer signal, to produce an estimated microphone signal.

Abstract: An audio system, including an echo canceler being configured to receive a first reference signal and a microphone signal, and to minimize an echo signal of the microphone signal, according to the first reference signal, the echo signal being a component of the microphone signal correlated to the first reference signal, to produce a residual signal; a post filter configured to receive a second reference signal and the residual signal, and to suppress at least one residual component correlated to the second reference signal, according to the second reference signal, to produce an estimated voice signal, wherein the first reference signal is received from a first location of an audio processing chain and the second reference signal is received from a second location of the audio processing chain, the first location and the second location being separated by at least one audio processing module of the audio processing chain.

Abstract: A noise reduction system includes sensors configured to generate an input signal, an adaptive filter configured to represent a transfer function of a path traversed by the input signal, one or more processing devices, and one or more transducers. The processing devices receive the input signal and generate an updated set of filter coefficients of the adaptive filter by separating the input signal into frequency subbands; determining for each subband, coefficients of a corresponding subband adaptive module; and combining the coefficients of multiple subband adaptive modules. Determining the coefficients of the corresponding subband adaptive module includes selecting a subset of a precomputed set of filter coefficients of the adaptive filter. The processing devices process a portion of the input signal using the updated set of filter coefficients of the adaptive filter to generate an output that destructively interferes with another signal traversing the path represented by the transfer function.

Abstract: An audio system includes: a head unit comprising at least a first processor, the head unit being configured to generate a plurality of program content signals, one of the plurality of program content signals being a phone program content signal being received from a phone, wherein the plurality of program content signals are transduced by an acoustic transducer into an acoustic signal within a vehicle cabin; a microphone disposed within the vehicle cabin such that the microphone receives the acoustic signal and produces a microphone signal comprising a plurality of echo signals; and a multichannel echo-cancellation unit being implemented by a second processor, the multichannel echo-cancellation unit being configured to receive a plurality of reference signals and to minimize the plurality of echo signals, according to the plurality of reference signals, to produce an estimated voice signal, and to provide the estimated voice signal to the head unit.

Abstract: An input signal representative of an undesired acoustic noise in a region is captured by one or more first sensors and processed to generate a cancellation signal. An output signal is generated based on the cancelation signal to cause one or more acoustic transducers to cancel, at least in part, the undesired acoustic noise in the region. A feedback signal representative of residual acoustic noise in the region is captured by one or more second sensors. A characteristic of each of the feedback signal, the cancellation signal, and a combination of the cancellation signal and the feedback signal is determined. One or more thresholds are compared to a ratio of (i) the characteristic of the combination of the cancellation signal and the feedback signal and (ii) a combination of the characteristic of the feedback signal and the characteristic of the cancellation signal to determine a convergence state.

Abstract: An acoustic device includes at least one acoustic transducer disposed such that, in a head-worn state, the at least one acoustic transducer is in an open-ear configuration in which an ear canal of a user of the acoustic device is unobstructed. The acoustic device also includes an array of two or more first microphones that captures audio preferentially from a first direction as compared to at least a second direction different from the first direction, wherein the audio captured using the array is processed and played back through the at least one acoustic transducer, and an active noise reduction (ANR) engine that includes one or more processing devices. The ANR engine is configured to generate a driver signal for the at least one acoustic transducer, the driver signal having phases that reduce effects of audio captured from at least the second direction.

Abstract: A noise reduction system includes sensors configured to generate an input signal, an adaptive filter configured to represent a transfer function of a path traversed by the input signal, one or more processing devices, and one or more transducers. The processing devices receive the input signal and generate an updated set of filter coefficients of the adaptive filter by separating the input signal into frequency subbands; determining for each subband, coefficients of a corresponding subband adaptive module; and combining the coefficients of multiple subband adaptive modules. Determining the coefficients of the corresponding subband adaptive module includes selecting a subset of a precomputed set of filter coefficients of the adaptive filter. The processing devices process a portion of the input signal using the updated set of filter coefficients of the adaptive filter to generate an output that destructively interferes with another signal traversing the path represented by the transfer function.

Abstract: Audio systems and methods for suppressing residual echo are provided. First and second audio program content signals are received, and a residual signal from an echo canceler is received. A first spectral mismatch is determined based at least upon a cross power spectral density of the first program content signal and the residual signal. The first spectral mismatch is associated with an operational state of the audio system. The residual signal is filtered to reduce residual echo, based at least upon the first spectral mismatch, a spectral density of the first program content signal, and a spectral density of the residual signal.

Abstract: An audio system, including an echo canceler being configured to receive a first reference signal and a microphone signal, and to minimize an echo signal of the microphone signal, according to the first reference signal, the echo signal being a component of the microphone signal correlated to the first reference signal, to produce a residual signal; a post filter configured to receive a second reference signal and the residual signal, and to suppress at least one residual component correlated to the second reference signal, according to the second reference signal, to produce an estimated voice signal, wherein the first reference signal is received from a first location of an audio processing chain and the second reference signal is received from a second location of the audio processing chain, the first location and the second location being separated by at least one audio processing module of the audio processing chain.