Acoustic noise reduction (ANR) headphones described herein have current detection circuitry that is used to detect current consumed by ANR circuitry as a result of pressure changes due to a tapping of a headphone, ear or head of a user. Tapping may be performed to change an audio feature or operating mode. The current detection circuitry senses a characteristic of the current that can be used to determine an occurrence of a tap event. Examples of a characteristic include an amplitude, waveform or duration of the sensed current. Advantageously, the ANR headphones avoid the need for control buttons to initiate the desired changes to the audio feature or operating mode. Error detection circuitry included in the ANR headphones can distinguish between a valid tap events and an occurrence of a different type of event that may otherwise be improperly be interpreted as a tap event.

A personal audio device, such as a wireless telephone, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal from a reference microphone signal and injects the anti-noise signal into the speaker or other transducer output to cause cancellation of ambient audio sounds. An error microphone is also provided proximate to the speaker to provide an error signal indicative of the effectiveness of the noise cancellation. A secondary path estimating adaptive filter is used to estimate the electro-acoustical path from the noise canceling circuit through the transducer so that source audio can be removed from the error signal. A level of the source audio with respect to the ambient audio is determined to determine whether the system may generate erroneous anti-noise and/or become unstable.

A system includes a first earpiece having an earpiece housing configured to isolate an ambient environment from a tympanic membrane by physically blocking ambient sound, a microphone disposed within the housing and configured to receive a first ambient audio signal from the ambient environment, a processor operatively connected to the microphone wherein the processor is configured to receive the first ambient audio signal from the microphone and determine if the first ambient signal exceeds a threshold sound level, and a speaker operatively connected to the processor. In a first mode of operation the processor determines that the first ambient audio signal exceeds the threshold sound level and processes the first ambient audio signal to modify the first ambient audio signal. In a second mode of operation the processor determines that the first ambient audio signal does not exceed the threshold sound level and reproduces the first ambient audio signal at the speaker.

An active noise control device includes a control signal generating unit including a first adaptive filter configured to generate a control signal by performing a filtering process on a reference signal corresponding to noise, an identifying unit configured to identify a peak frequency in an impedance frequency characteristic of an actuator, a peak frequency storage unit configured to store an initial peak frequency of the actuator, a first determination unit configured to determine whether or not a difference between the peak frequency currently identified and the initial peak frequency is greater than or equal to a threshold value, and a control unit configured to change a characteristic of the control signal generated by the control signal generating unit when the first determination unit determines that the difference is greater than or equal to the threshold value.

An active noise cancellation (ANC) system may include an adaptive filter divergence detector for detecting divergence of the one or more controllable filters as they adapt, based on dynamically adapted thresholds. Upon detection of a controllable filter divergence, the ANC system may be deactivated, or certain speakers may be muted. Alternatively, the ANC system may modify the diverged controllable filters to restore proper operation of the noise cancelling system.

An earphone includes a feedforward microphone located outside ear and a feedback microphone located inside ear. A method for recognizing wind noise of the earphone includes: feedforward microphone signal collected by feedforward microphone and feedback microphone signal collected by feedback microphone are acquired; Fourier transform is performed on feedforward and feedback microphone signals to obtain a feedforward microphone frequency domain signal and a feedback microphone frequency domain signal; inverse feedback filtering processing is performed on the feedback microphone frequency domain signal to obtain an inverse feedback filtering processing result; inverse feedforward filtering processing is performed on the feedforward microphone frequency domain signal and the inverse feedback filtering processing result to obtain an inverse hybrid filtering processing result; and a wind noise recognition result of the earphone is obtained based on an interrelationship between the inverse feedback filtering processing result and the inverse hybrid filtering processing result.

An earphone includes a first microphone located outside an ear and a second microphone located inside the ear. A method for recognizing wind noise of the earphone includes: a first microphone signal collected by the first microphone and a second microphone signal collected by the second microphone are acquired; a first frequency domain filtered signal is obtained based on the first microphone signal and the second microphone signal; and obtaining a wind noise recognition result of the earphone based on coherence between the first microphone signal and the first frequency domain filtered signal.

A system includes a microphone unit coupled to a roof of an autonomous vehicle. The microphone unit includes a microphone board having a first opening. The microphone unit also includes a first microphone positioned over the first opening and coupled to the microphone board. The microphone unit further includes an accelerometer. The system also includes a processor coupled to the microphone unit.

A noise reduction device includes a processor that converts a noise signal collected by a microphone disposed in a control space into a noise signal in a frequency domain, a storage that stores the converted noise signal in the frequency domain as a reference signal, and a signal generator that generates a noise reduction signal for reducing the noise signal collected by the microphone at a control position of the control space. The processor determines whether or not the noise signal is non-stationary noise based on a frequency characteristic of the converted noise signal in the frequency domain and a frequency characteristic of the reference signal. When it is determined that the noise signal is the non-stationary noise, the processor controls the signal generator so as to cancel generation of the noise reduction signal.

An earphone includes a feedforward microphone located outside ear and a feedback microphone located inside ear. A method for recognizing wind noise of the earphone includes: feedforward microphone signal collected by feedforward microphone and feedback microphone signal collected by feedback microphone are acquired; Fourier transform is performed on feedforward and feedback microphone signals to obtain a feedforward microphone frequency domain signal and a feedback microphone frequency domain signal; inverse feedback filtering processing is performed on the feedback microphone frequency domain signal to obtain an inverse feedback filtering processing result; inverse feedforward filtering processing is performed on the feedforward microphone frequency domain signal and the inverse feedback filtering processing result to obtain an inverse hybrid filtering processing result; and a wind noise recognition result of the earphone is obtained based on an interrelationship between the inverse feedback filtering processing result and the inverse hybrid filtering processing result.