An audio customization system responsive to one or more inputs that enhance aspects of an audio output and one or more inputs that diminish aspects of an audio output. The system is set up to be able to lessen the influence of ambient audio or in some situations enhance ambient audio over source audio. The system may specify aspects of audio to be modified by specification of filtering algorithm, characterization of audio samples, monitored distortion, user selection, location specification or environmental specification.

A noise reducing sound reproduction system comprises a loudspeaker that is connected to a loudspeaker input path and that radiates noise reducing sound. A microphone is connected to a microphone output path and picks up the noise or a residual thereof. An active noise reduction filter is connected between the microphone output path and the loudspeaker input path, and the active noise reduction filter comprises at least one shelving filter.

Audio pickup systems and methods are provided to enhance an audio signal by removing noise components related to an acoustic environment. The systems and methods receive a primary signal and one or more reference signals from various microphones. Adaptive filtering and combining minimizes an energy content of a resulting output signal, e.g., to form a substantially null output when the system is in a static acoustic environment. When the system is a playback sound source, one or more echo cancellers may contribute to removing content from the output signal. A change in the acoustic environment, such as a new sound source, causes content in the output signal until the adaptive filtering adapts to the new environment. In some examples, a desired content such as a wake-up word is detected and adaptation is stopped.

A noise reduction device includes a plurality of noise microphones, noise controller, and control speakers. Noise controller generates a control-sound signal to reduce a noise, at a control center of a control space, with the noise being detected by the plurality of noise microphones. Noise microphone disposed at a shorter distance from the control center than distance “d” indicated by Relational Expression (1) is smaller in number than noise microphones disposed at longer distances than distance “d” where “λ” is a wavelength corresponding to control upper-limit frequency “f” in noise microphones, “d0” is a distance from the control center to control speakers, “t” is a control delay time in control speakers, and “v” is a sound speed.
d=d0+t×v−λ/2  (1)

A signal processing device includes a coefficient updater configured to calculate a filter coefficient based on a reference signal, an error signal, and an update parameter to set the filter coefficient in a noise cancelling filter. A parameter adjuster adjusts the update parameter according to fluctuation of the reference signal produced from an output of a reference microphone.

An active noise control device controls a speaker so as to output a canceling sound for canceling noise transmitted from a vibration source. The active noise control device includes a control signal generating unit configured to perform signal processing on a basic signal corresponding to a predetermined frequency by a feedback filter and a extraction filter, which is an adaptive notch filter, to generate a control signal that control the speaker, a secondary path filter updating unit configured to update sequentially and adaptively a secondary path filter, and a feedback filter setting unit configured to set the feedback filter based on the secondary path filter.

A sound processing apparatus includes a first microphone which acquires environmental sound, a second microphone which acquires sound of a noise source, and a CPU which causes the sound processing apparatus to function as a noise detection unit configured to generate a noise signal of the noise source according to a sound signal from the second microphone, the noise detection unit reducing sound other than noise of the noise source from the sound signal from the second microphone and generating the noise signal, and a noise reducing unit configured to reduce the noise of the noise included in a sound signal from the first microphone using the sound signal from the noise detection unit.

An acoustic echo canceller (AEC) uses a simulated echo from an adaptive filter to cancel an actual echo from a real environment. The echo cancellation is optimal when the adaptive filter response accurately matches the environment response. This can be achieved by changing coefficients of the filter in a step-wise fashion until the filter is converged on a configuration that provides optimal results. The convergence of the filter can be negatively affected by interference due to a double talk event or by an event in which the environment is changed. The disclosed AEC is configured to respond to these disruptive events by adjusting a step-size of the adaptive algorithm used to change the coefficients.

An active noise reduction system using adaptive filters. A method of operation the active noise reduction system includes smoothing a stream of leakage factors. The frequency of a noise reduction signal may be related to the engine speed of an engine associated with the system within which the active noise reduction system is operated. The engine speed signal may be a high latency signal and may be obtained by the active noise reduction system over audio entertainment circuitry.

A method for operating a hearing device for being worn at least partially within an ear canal of a user, including an ear canal microphone, a filtering unit and an electrical-to-acoustical converter, capable of active occlusion control (AOC) and allowing the user to adjust the AOC functionality according to his or her preferences. The method includes picking up an ear canal internal sound at the microphone which provides a signal representative of the internal sound, filtering the signal with the filtering unit to reduce a perceived level of body sounds produced by the user, providing the filtered signal to the converter which outputs sound into the ear canal, and changing at least one setting or parameter of the filtering unit in dependence of a control signal, wherein the control signal is initiated by the user. Moreover, a hearing device adapted to perform the method is provided.