A method and system directed to controlling audio devices with active noise reduction. The system detects an instability condition in a first headphone; generates one or more control signals to adjust one or more ANR parameters of the first headphone using a first controller, wherein the one or more ANR parameters are adjusted to change the first headphone from a first ANR state to a second ANR state to mitigate the instability condition; and synchronizes the one or more ANR parameters of the first headphone with second headphone. In an example, the system returns the first headphone to the first ANR state after detecting that the first headphone was removed from an ear of a user at the first time and detecting that the first headphone was engaged with the ear at the second time.

An audio system attachable to a computer includes a sound reproduction device for producing audible sound from audio signals. The sound reproduction device includes a radio tuner and a powered speaker. The audio system further includes a connector for connecting the sound reproduction device with a computer. The computer provides audio signals from a plurality of sources, the sources including a computer CD player, digitally encoded computer files stored on the computer, and a computer network connected to the computer. The sound reproduction device further includes control buttons for controlling at least one of the computer CD player, the digitally encoded computer files and the computer network.

An audio output device controls the application of active noise cancellation (ANC) levels based on a current status of the device. The audio output device includes a communication interface configured to provide a wired or wireless connection to a playback device, a signal detector configured to detect an audio signal provided through the communication interface, an ANC module configured to apply a first-level ANC to the audio signal, and a control unit configured to determine a level of the ANC to be applied by the ANC module. Upon determining that the audio signal is not provided based on information provided from at least one of the communication interface or the signal detector, the control unit instructs the ANC module to perform a second-level ANC.

An adaptive noise canceling (ANC) circuit adaptively generates an anti-noise signal from a reference microphone signal that is injected into the speaker or other transducer output to cause cancellation of ambient audio sounds. An error microphone proximate the speaker provides an error signal. A secondary path estimating adaptive filter estimates the electro-acoustical path from the noise canceling circuit through the transducer so that source audio can be removed from the error signal. Tones in the source audio, such as remote ringtones, present in downlink audio during initiation of a telephone call, are detected by a tone detector using accumulated tone persistence and non-silence hangover counting, and adaptation of the secondary path estimating adaptive filter is halted to prevent adapting to the tones. Adaptation of the adaptive filters is then sequenced so any disruption of the secondary path adaptive filter response is removed before allowing the anti-noise generating filter to adapt.

A personal audio device, such as a wireless telephone, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal from an output of a microphone that measures ambient audio. The anti-noise signal is combined with source audio to provide an output for a speaker. The anti-noise signal causes cancellation of ambient audio sounds that appear at the microphone. A processing circuit estimates a level of background noise from the microphone output and sets a power conservation mode of the personal audio device in response to detecting that the background noise level is lower than a predetermined threshold.

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.

The present disclosure provides a method for evaluating an electronic device. The method comprises determining, with an acoustic tube, a value of a first parameter, the value of the first parameter being indicative of the acoustic impedance of a reference termination. The method further comprises determining, with the acoustic tube, a value of a second parameter, the value of the second parameter being indicative of the acoustic impedance of the reference termination, when occluded by the electronic device. The method then comprises calculating a value of a third parameter, the value of the third parameter being indicative of the acoustic impedance of the electronic device, based on the value of the first parameter and the value of the second parameter.

Active noise cancellation systems and methods include a feedforward path configured to receive a reference signal comprising ambient noise and adaptively generate an anti-noise signal to cancel the ambient noise. The adaptive filter is tuned in accordance with at least one parameter, which is set by a logic device configured to determine an ambient noise condition based the reference signal by estimating a fullband power of the reference signal, estimating a low-frequency power of the reference signal, comparing the fullband power and low-frequency power to one or more thresholds, and/or setting one or more ambient noise flags. The ambient noise condition may include a quiet background, a wideband noise condition, and/or a low-frequency dominant noise condition.

Disclosed herein are methods for operating an apparatus for generating acoustic compensation signals used to compensate acoustic signals from operation of a motor-vehicle engine, comprising the steps: providing an EOC device, which is designed to generate acoustic compensation signals used to compensate acoustic signals that result from the operation of the engine; providing a device configured using the EOC device as a model; determining at least one audio signal to be output into a passenger compartment of a motor vehicle by means of an audio output device, before said audio signal is captured by an audio capturing element associated with the EOC device; applying an evaluation specification to evaluate the at least one audio signal with respect to at least one evaluation criterion; generating evaluation information with respect to the at least one evaluation criterion; controlling the operation of the EOC device on the basis of the evaluation Information.

A method and system directed to controlling audio devices with active noise reduction. The system detects a first instability condition in a first headphone based on one or more parameters; alters a parameter of the one or more parameters; and detects a second audio instability condition in the first headphone based on the altered parameter of the one or more parameters. The first and second audio instability conditions are related to audio feedback.