A road noise cancellation (RNC) system may include a controller and attenuator for reducing the audibility of the noise floor caused by the system's vibration sensors. A level of anti-noise at a location in a passenger cabin that may be attributed to the sensor noise floor may be estimated. An actual sound level in the passenger cabin may be measured or estimated, with the sensor noise floor component algorithmically removed. The difference in levels may be compared to a predetermined threshold to determine an amount of attenuation, if any, to be applied to an anti-noise signal to reduce audibility.

A method for operating a hearing device including a component to be worn at least partially in an ear of a user and an active noise control (ANC) system is provided. The method includes capturing an audio with a microphone system, generating an audio signal based on the captured audio, and generating a feed-forward (FF) compensating signal based on the captured audio. The method includes monitoring the acoustic environment of the hearing device for presence of wind noise, and mixing the audio signal with the generated FF compensating signal at a ratio dependent on whether wind noise is detected to provide an acoustic output signal. A hearing device including an active noise control (ANC) system and a wind noise monitor is also provided.

A system and method for disabling adaptation in an adaptive feedforward control system at low speeds. The method includes generating a noise signal representative of undesired noise detected by a noise sensor of a vehicle and generating a noise-cancellation signal via a controller within the vehicle. Residual noise resulting from the combination of the acoustic energy of the noise-cancellation signal and the undesired noise is detected by a reference sensor, which generates an error signal based on the residual noise. The error signal and a speed signal from a speed sensor on the vehicle are transmitted to an adaptive processing module for the generation of a filter update signal. The adaptive processing module selectively permits or prevents the filter update signal to adapt filter coefficients of a filter when the speed signal is within a set of conditions.

An integrated circuit for implementing at least a portion of a personal audio device may include an output for providing an output signal to a transducer, wherein the output signal includes a pilot signal, a microphone input for receiving a microphone signal from a microphone indicative of an output of the transducer, and a processing circuit. The processing circuit may be configured to implement a pilot signal control to apply an adjustment to the pilot signal as necessary to maintain the pilot signal at a substantially constant magnitude regardless of proximity of the transducer to a pinna and implement a proximity determination block configured to determine proximity of the transducer to the pinna based on the adjustment.

Aspects are generally directed to headphone systems that adjust Active Noise Reduction operations based on measurements of environmental conditions. In one example, a headphone system includes an earpiece having an interior volume, the earpiece configured to couple to an ear and define an acoustic volume including the interior volume and a volume within the ear, a speaker to provide acoustic energy to the acoustic volume based on a received driver signal, a feedback microphone to detect at least residual noise within the acoustic volume and generate a feedback audio signal indicative of the residual noise, and a control circuit including a sensor interface configured to receive an atmospheric pressure signal, the control circuit coupled to the feedback microphone to receive the feedback audio signal, and the control circuit configured to adjust the driver signal based at least in part on the feedback audio signal and the atmospheric pressure signal.

A method for calibrating an ANC-enabled portable audio device having microphones plays continuously a calibration sound by a calibrated speaker of a test station separate from the device. For each microphone of all the microphones, a microphone calibration value is computed using a comparison of a predetermined level and a measured level of an audio signal transduced by the microphone in response to the continuously-played calibration sound. The calibration is done without using a microphone of the test station. A processing element of the device may be programmed to make the comparison and computation. The processing element also causes a speaker of the device to generate a second calibration sound, measures a second level while the computed calibration value is applied to one of microphones (e.g., error microphone), and computes a calibration value for the device speaker using a comparison of a predetermined level and the second level.

A sound control device in a vehicle and control method thereof may include obtaining energy per unit time of an audio signal corresponding to a preset low frequency band, calculating an allowable reference value based on a difference between a magnitude of energy per unit time of the audio signal and a magnitude of a preset maximum allowable input of a speaker, monitoring whether a magnitude of energy per unit time of a noise control signal for eliminating noise in the vehicle exceeds the allowable reference value, and adjusting a magnitude of the noise control signal when the magnitude of energy per unit time of the noise control signal exceeds the allowable reference value.

Audio devices and methods are provided for detecting instability in an associated feedforward audio processing system. A microphone provides a feedforward signal for processing by a feedforward filter. The processed signal may provide noise reduction and/or sound enhancement associated with the surrounding environment. The processed signal contributes to a driver signal provided to an acoustic transducer, e.g., a driver, to produce acoustic signals for a user. A processor is configured to detect an indication of instability in one or more of the signals, and to adjust a phase response of the feedforward signal path in response to detecting the indication of instability.

Methods and systems are provided for an automatic noise control system. Automatic noise control includes evaluating an amplitude of an acceleration acting on an acceleration sensor and generating a reference signal representative of the amplitude of the acceleration, the acceleration being representative of unwanted noise sound generated by a noise source, filtering the reference signal with a noise control transfer function to generate an anti-noise signal, and converting with a loudspeaker the anti-noise signal into anti-noise sound.

An active road-noise control system and method include using a sensor arrangement to generate a first sense signal representative of at least one acceleration, motion and/or vibration that occurs at a first position on a vehicle body and a second sense signal representative of sound that occurs at a second position within the vehicle body; they also provide a noise-reducing signal by processing the sense signals according to a first or a second mode of operation. They include the generation of noise-reducing sound within the vehicle body at the second position from the noise reducing signal and the operational state of the sensor arrangement; the first sense signal and the second sense signal are processed in the first mode when the sensor arrangement is in a proper operational state and in the second mode when a malfunction of the sensor arrangement has been detected.