A system and method for quieting unwanted sound. As a non-limiting example, various aspects of this disclosure provide a system and method, for example implemented in a premises-based or home audio system, for quieting unwanted sound at a particular location.

In a first system signal processing unit, a first system auxiliary filter generates a correction signal for correcting an error signal from a noise signal, a first system subtractor subtracts the correction signal from an output of a first microphone to obtain an error signal, an adaptive filter performs an adaptive operation using the error signal to generate a cancel sound output from a first speaker, and a DMS detects a position of a user's ear. When the position of the user's ear moves, the controller stops the adaptive operation, updates the transfer function of the first system auxiliary filter to the transfer function corresponding to the noise cancel position matching the position of the user's ear, gradually changes the transfer function of the adaptive filter to the transfer function corresponding to the matching noise cancel position, and resumes the adaptive operation after the change is completed.

For example, an apparatus for Active Acoustic Control (AAC) of an open acoustic headphone may include an input to receive input information including a residual-noise input including residual-noise information corresponding to a residual noise sensor of the open acoustic headphone, and a noise input including noise information corresponding to a noise sensor of the open acoustic headphone; a controller configured to determine a sound control pattern configured for AAC of the open acoustic headphone, the controller configured to identify a mounting-based parameter of the open acoustic headphone based on the input information, and to determine the sound control pattern based on the mounting-based parameter, the residual-noise input, and the noise input; and an output to output the sound control pattern to an acoustic transducer of the open acoustic headphone.

A method of operating a headphone configured to be removed from and placed in close proximity to a user's ear can include generating an input signal by an input signal generating device. The method can also include determining whether an insertion event has occurred based on the generated input signal and causing the headphone to operate in 5 a low power mode responsive to an absence of an insertion event determination after a first period of time. The method can also include causing the headphone to operate in an ultra-low power mode responsive to the absence of an insertion event determination after a second period of time that occurs after the first period of time, the ultra-low power mode having a lower power consumption than the low power mode.

An acoustic processing apparatus includes a sensor that detects deformation of an attachment unit attached to an ear portion of a user, and a control unit that switches a mode for noise cancelling in accordance with a detection result of deformation of the attachment unit.

An active noise reduction device includes: a reference signal input terminal that receives a reference signal outputted by a reference signal source and having a correlation with noise in a space in an automobile, the reference signal source being attached to the automobile; a test signal source that outputs a test signal to a loudspeaker attached to the automobile, the loudspeaker being used to output a canceling sound for reducing the noise; and an anomaly determiner that determines whether the reference signal source has an anomaly, based on the reference signal inputted from the reference signal source to the reference signal input terminal when the test signal is outputted to the loudspeaker.

For example, an apparatus for Active Acoustic Control (AAC) of an open acoustic headphone may include an input to receive input information including a residual-noise input including residual-noise information corresponding to a residual noise sensor of the open acoustic headphone, and a noise input including noise information corresponding to a noise sensor of the open acoustic headphone; a controller configured to determine a sound control pattern configured for AAC of the open acoustic headphone, the controller configured to identify a mounting-based parameter of the open acoustic headphone based on the input information, and to determine the sound control pattern based on the mounting-based parameter, the residual-noise input, and the noise input; and an output to output the sound control pattern to an acoustic transducer of the open acoustic headphone.

Provided is a speaker unit that constitutes a sound system that reduces noise in an open space, including: a housing; a driver; and a microphone, in which the microphone and the driver are provided in the housing such that sensitivity of the microphone to a signal output from the driver is lower.

A 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 various temporal or frequency domain amplitude characteristics. 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. This may include adjusting a leakage value of an adaptive filter controller.

A system for reducing noise for a user includes a first detector configured to generate a first noise signal, wherein the first noise signal is a representation of a first noise that is transmitted to the user through a first sound pathway, and a second detector configured to generate a second noise signal, wherein the second noise signal indicates a second noise perceived by the user. The system also includes a processor configured to determine a noise correction signal based on the first noise signal and/or the second noise signal, and a speaker configured to generate a sound for reducing the noise based on the noise correction signal.