Differing from conventionally-used exhaust pipe utilizing discontinuous section area(s) and sound-absorbing material(s) to abate the noise produced by an engine, the present invention provides a waste air exhausting device consisting of: a housing, a supporting plate disposed in the housing, a miniature microphone disposed at the end of the housing, and a loudspeaker disposed on the supporting plate. Therefore, according to the noise produced by the engine, a noise controller system coupling to the miniature microphone and the loudspeaker is able to produce an anti-noise signal through the loudspeaker for abating the engine noise. On the other hand, the noise controller system can also produce an anti-noise signal having specific frequencies components according to the frequency of the engine noise and a reference signal, so as to modulate the frequency of the engine noise by broadcasting the anti-noise signal having the specific frequencies components in the housing through the loudspeaker.

Example techniques involve noise-robust acoustic echo cancellation. An example implementation may involve causing one or more speakers of the playback device to play back audio content and while the audio content is playing back, capturing, via the one or more microphones, audio within an acoustic environment that includes the audio playback. The example implementation may involve determining measured and reference signals in the STFT domain. During each n.sup.th iteration of an acoustic echo canceller (AEC): the implementation may involve determining a frame of an output signal by generating a frame of a model signal by passing a frame of the reference signal through an instance of an adaptive filter and then redacting the n.sup.th frame of the model signal from an n.sup.th frame of the measured signal. The implementation may further involve determining an instance of the adaptive filter for a next iteration of the AEC.

Certain example embodiments relate to an acoustic wall assembly that uses active and/or passive sound reverberation to achieve noise-disruptive functionality, and/or a method of making and/or using the same. With the active approach, sound waves in a given frequency range are detected by a sound masking circuit. Responsive to detection of such sound waves, an air pump (e.g., speaker) is used to pump air in the wall assembly to actively mask the detected sound waves via reverberation and/or the like. The wall assembly may include one, two, or more walls, and the walls may be partial or full walls. With the passive approach, sound waves in a given frequency range are disrupted via features (e.g., holes, slits, etc.) formed in and/or on a wall itself. These techniques may be used together or separately, in different example embodiments.

Certain example embodiments relate to an acoustic wall assembly that uses active and/or passive sound reverberation to achieve noise-disruptive functionality, and/or a method of making and/or using the same. With the active approach, sound waves in a given frequency range are detected by a sound masking circuit. Responsive to detection of such sound waves, an air pump (e.g., speaker) is used to pump air in the wall assembly to actively mask the detected sound waves via reverberation and/or the like. The wall assembly may include one, two, or more walls, and the walls may be partial or full walls. With the passive approach, sound waves in a given frequency range are disrupted via features (e.g., holes, slits, etc.) formed in and/or on a wall itself. These techniques may be used together or separately, in different example embodiments.

Certain example embodiments relate to an acoustic wall assembly that uses active and/or passive sound reverberation to achieve noise-disruptive functionality, and/or a method of making and/or using the same. With the active approach, sound waves in a given frequency range are detected by a sound masking circuit. Responsive to detection of such sound waves, an air pump (e.g., speaker) is used to pump air in the wall assembly to actively mask the detected sound waves via reverberation and/or the like. The wall assembly may include one, two, or more walls, and the walls may be partial or full walls. With the passive approach, sound waves in a given frequency range are disrupted via features (e.g., holes, slits, etc.) formed in and/or on a wall itself. These techniques may be used together or separately, in different example embodiments.

Noise abatement within a signal stream containing unwanted signal referred to as noise is performed by acquiring a digitized noise signal and using a digital processor circuit to subdivide the acquired noise signal into different frequency band segments and thereby generate a plurality of segmented noise signals. Then individually for each segmented noise signal, the processor shifts in time the segmented noise signal by an amount dependent on a selected frequency of the segmented noise signal to produce a plurality of shifted segmented noise signals. The precise time shift applied to each noise segment considers the frequency content of the segment and the system processing time. Individually for each segmented noise signal, amplitude scaling is applied. The shifted and amplitude-scaled segmented noise signals are then combined to form a composite anti-noise signal which is output into the signal stream to abate the noise through destructive interference.

An apparatus includes a hybrid adaptive active noise control unit (HAANCU) configured to provide an anti-noise signal to an ear speaker from a reference noise signal of a reference microphone and an error signal of an error microphone, a decimator configured to decimate the reference noise signal and error signal, an adaptive hybrid ANC training unit (AHANCTU) including at least one noise cancellation filter and a filter configured to provide a feedback signal to the at least one noise cancellation, which trains parameters of the AHANCTU based on the decimated reference noise signal, the decimated error signal, and the feedback signal. The apparatus further includes a rate conversion unit configured to up-sample the parameters and update the HAANCU with the up-sampled parameters.

Embodiments of the present application provide a method and system for active noise control, which can meet different needs of different consumers on sound quality of headphones. The method includes: determining an expected noise control curve of performing active noise control on a target object; determining a target filter according to the expected noise control curve and a filter model; and performing noise control processing on an external noise signal using the target filter.

A design method for feedforward active noise control system is disclosed. Based on a target signal and a reference signal, a first adaptive system identifying unit is enabled to complete a first system identification process for producing a first adaptive filter, and then a second adaptive system identifying unit is enabled to complete a second system identification process for producing a second adaptive filter. After the second adaptive filter is converted to a digitally-controlled filter by using a system identification tool, the digitally-controlled filter is implemented into a DSP chip of a feedforward active noise control system. As a result, it is able to find that not only the computing loading of the DSP chip is significantly lowered while an adaptive algorithm executes an active noise control computing, but also the feedforward active noise control system exhibits a broad frequency bandwidth noise cancelling ability.

A method and device for noise-reduction processing and an earphone are disclosed. The method includes: collecting an environmental-sound signal by using a feedforward microphone to acquire amplitude information and spectrum information of the environmental-sound signal; performing feedforward noise-reduction processing on the environmental-sound signal according to the amplitude information of the environmental-sound signal, and extracting a sound signal having a specified frequency in the environmental-sound signal according to the spectrum information of the environmental-sound signal; and outputting the sound signal having the specified frequency together with the signal after being feedforward noise-reduction processed. The present disclosure can realize the monitoring of the valuable sound signal having a specified frequency in the environmental-sound signal.