An apparatus includes a hybrid adaptive active noise control unit (HAANCU) configured to provide an anti-noise signal to an ear speaker from a reference noise signal of a reference microphone and an error signal of an error microphone, a decimator configured to decimate the reference noise signal and error signal, an adaptive hybrid ANC training unit (AHANCTU) including at least one noise cancellation filter and a filter configured to provide a feedback signal to the at least one noise cancellation, which trains parameters of the AHANCTU based on the decimated reference noise signal, the decimated error signal, and the feedback signal. The apparatus further includes a rate conversion unit configured to up-sample the parameters and update the HAANCU with the up-sampled parameters.

An engine harmonic cancellation system includes an accelerometer disposed within a vehicle to detect a harmonic produced by an engine of the vehicle and to produce a harmonic reference signal representative of the harmonic; a controller configured to produce a harmonic cancellation signal that, when transduced into an acoustic signal, cancels the harmonic within at least one cancellation zone within a cabin of the vehicle, wherein the harmonic cancellation signal is based, at least in part, on mixing the harmonic reference signal converted to baseband with a baseband signal output from a look up table; and a speaker disposed within the cabin and configured to receive the harmonic cancellation signal and to transduce the harmonic cancellation signal into an acoustic harmonic cancellation signal, such that the harmonic is cancelled within the cancellation zone.

A method and system for daisy chaining tournament audio controllers, where the method comprises, in a headset coupled to a first audio controller, the first audio controller being in a daisy chain of audio controllers: receiving a chat signal from a second audio controller in the daisy chain of audio controllers, receiving a microphone signal from a microphone in the headset, summing the chat signal with the microphone signal, communicating the summed signal to a third audio controllers in the daisy chain, and communicating the chat signal to the headset. The microphone signal may be removed from the summed chat signal and microphone signal by adding a second microphone signal 180 degrees out of phase with the microphone signal. The chat signal may be summed with the microphone signal at an amplitude set by a user of the headset after the removal of the microphone signal.

A method performed by a wearable audio output device worn by a user is provided for controlling external noise attenuated by wearable audio output device. A speech is detected from a user wearing the wearable audio output device, wherein the audio output device has active noise reduction turned on. It is determined, based on the detecting, that the user desires to speak to a subject in the vicinity of the user. In response to the determining, a level of noise reduction is reduced to enable the user to hear sounds external to the audio output device. It is determined that the user desires to speak to the subject by detecting at least one condition of a plurality of conditions.

A system performs pole-zero or IIR modeling and estimation of an inter-microphone transfer function between first and second microphones that output respective first and second microphone signals. The system includes a first adaptive FIR filter to which the first microphone signal is provided, a delay element that delays the second microphone signal by a predetermined delay amount, and a second adaptive FIR filter to which the delayed second microphone signal is provided. A first coefficient of the second adaptive FIR filter is constrained to a fixed non-zero value. The filters are jointly adapted to minimize an error signal that is a difference of the two filters outputs. The delay is small: approximately the acoustic propagation delay between the two microphones and is not determined by the environmental reverberation characteristics. The error signal may serve as a noise reference in a noise canceller, for implementing far-field beamforming with low delay.

A system and method for accurately estimating engine noise at a virtual microphone location, such as an occupant's ear position, in an acoustic space in order to enhance performance of an Engine Order Cancellation (EOC) system is provided. A set of weights and transfer functions that are dependent on various vehicle parameters, such as frequency, load, and speed, may be employed to estimate noise at a position where there are no physical microphones present. The accurate estimation of engine noise at virtual location, such as an occupant's ear position, may be achieved using a frequency dependent weighted sum of filtered and unfiltered error signals measured at microphones mounted at various locations inside an acoustic space, such as a vehicle cabin, which may not be located near virtual location.

Systems and methods are provided for an infant incubator having features for active noise cancellation, including enclosure designs, positioning systems, and error sensor selection.

Systems and methods are disclosed for identifying at least one cause of noise in a vehicle audio system. The vehicle audio system may include a plurality of audio channels. Acoustic output may be generated and received through each of the audio channels. Acoustic input may be received from one or more of the audio channels and may be processed to generate processed acoustic input. The processed acoustic input may include a frequency response of the acoustic input. The processed acoustic input may be compared to corresponding channel target input and at least one deviation may be determined. A cause of the at least one deviation may then be determined based on a relationship between the at least one deviation and a set of resolved indications of cause, each of the set of resolved indications of cause corresponding to at least one of a set of recorded causes.

A method and system for daisy chaining tournament audio controllers, where the method comprises, in a headset coupled to a first audio controller, the first audio controller being in a daisy chain of audio controllers: receiving a chat signal from a second audio controller in the daisy chain of audio controllers, receiving a microphone signal from a microphone in the headset, summing the chat signal with the microphone signal, communicating the summed signal to a third audio controllers in the daisy chain, and communicating the chat signal to the headset. The microphone signal may be removed from the summed chat signal and microphone signal by adding a second microphone signal 180 degrees out of phase with the microphone signal. The chat signal may be summed with the microphone signal at an amplitude set by a user of the headset after the removal of the microphone signal.

A method performed by a wearable audio output device worn by a user is provided for controlling external noise attenuated by wearable audio output device. A speech is detected from a user wearing the wearable audio output device, wherein the audio output device has active noise reduction turned on. It is determined, based on the detecting, that the user desires to speak to a subject in the vicinity of the user. In response to the determining, a level of noise reduction is reduced to enable the user to hear sounds external to the audio output device. It is determined that the user desires to speak to the subject by detecting at least one condition of a plurality of conditions.