A system and method for removal of unwanted vibration noise are provided. The system may detect, by a microphone(s) of the system, at least one audio signal including audio content output from at least one speaker and other audio data from one or more other sources, or caused by the one or more other sources. The other audio data may include determined undesirable vibration noise causing distortion of the at least one audio signal. The system may determine, by at least one sensor of the system, a subset of the other audio data based in part on determining at least one motion of a user of the system, or motion of one or more other users. The system may remove, or reduce, the undesirable vibration noise from the at least one audio signal to enable output of sound associated with a modification of the at least one audio signal.

A method for cancelling ambient audio sounds in the proximity of a transducer may include receiving an error microphone signal indicative of the output of the transducer and ambient audio sounds at the transducer. The method may also include generating an anti-noise signal for countering the effects of ambient audio sounds at an acoustic output of the transducer, wherein generating the anti-noise signal comprises applying a feedback filter having a response that generates a feedback anti-noise signal based on the error microphone signal and applying a variable gain element in series with the feedback filter. The method may further include monitoring whether an ambient audio event is occurring that could cause the feedback filter to generate an undesirable component in the anti-noise signal and controlling the gain of the variable gain element to reduce the undesirable component.

A method performed by an audio output device is provided for detecting instabilities and taking mitigating actions. Specifically, an A-weighted dBA level of a raw feedback signal exceeding a threshold level trigger, at least, muting the driver. The described methods apply to detecting instabilities across a broad frequency spectrum.

An active noise cancellation method and active noise cancellation earphones are provided, which may improve a noise cancellation effect of the active noise cancellation earphones. The method includes: determining a first primary path transfer function according to a first out-of-ear data collected by the out-of-ear microphone and a first in-ear data collected by the in-ear microphone when the speaker plays audio data; determining audio data received by the in-ear microphone according to the first in-ear data, the first out-of-ear data and the first primary path transfer function; determining a first secondary path transfer function according to the audio data played through the speaker and the audio data received by the in-ear microphone; and updating an operation coefficient of the filter to a first operation coefficient according to the first primary path transfer function and/or the first secondary path transfer function.

A signal processing method and an acoustic system are provided. When M sound sensors in a sound sensor module are in operation, they collect an ambient sound and generate M sound pickup signals. The ambient sound comprises a first sound from a speaker and a second sound from a target sound source. A signal processing circuit can perform a filtering operation on the M sound pickup signals based on M sets of target filtering parameters to obtain M filtered signals, and perform a synthesis operation on the M filtered signals to obtain a composite signal, and then perform a target operation on the composite signal. Since the M sets of target filtering parameters are configured to minimize a signal component from the speaker in the composite signal under a target constraint.

Methods and systems are described for mitigating acoustic feedback via an open ear device. In various examples, systems or methods may receive, via a first microphone and a second microphone positioned on an open ear device, a first audio signal and a second audio signal, respectively. The first audio signal and second audio signal may be converted to a first digital audio signal and a second digital audio signal. The first digital audio signal and second digital audio signal may be independently processed by an AFC to reduce acoustic feedback. A beamformer may adjust the first digital audio signal and second digital audio signal based on a target direction to create a beamformer digital audio signal. The beamformer digital audio signal may be processed via feedforward processing to create a target audio. The target audio may be phase shifted and transmitted to a loudspeaker positioned on the open ear device.

Aspects include approaches for feedback instability control in wearable audio devices. In certain cases, a method of controlling feedback instability in a wearable audio device with an active noise reduction (ANR) system includes: determining a current feedback instability by combining outputs from multiple instability detectors, applying latch logic to the current feedback instability to determine a current mitigation value, and adjusting a driver command signal based on the current mitigation value to mitigate feedback instability.

The wearable device includes a sound producing device and a sound sensing device. The sound producing device produces a front radiating wave and a back radiating wave while producing the sound. The sound sensing device is disposed on a nodal position where the front radiating wave and the back radiating wave cancel each other on the nodal position.

Various aspects include approaches for feedback instability control in wearable audio devices. In certain cases, a method of controlling feedback instability in a wearable audio device with an active noise reduction (ANR) system includes: determining a current feedback instability by combining outputs from multiple instability detectors, applying latch logic to the current feedback instability to determine a current mitigation value, where the latch logic controls adjustment of the current mitigation value with a set of timers, and adjusting a driver command signal based on the current mitigation value to mitigate feedback instability.