A first input signal captured by one or more sensors associated with an ANR headphone is received. A frequency domain representation of the first input signal is computed for a set of discrete frequencies, based on which a set of parameters is generated for a digital filter disposed in an ANR signal flow path of the ANR headphone, the set of parameters being such that a loop gain of the ANR signal flow path substantially matches a target loop gain. Generating the set of parameters comprises: adjusting a response of the digital filter at frequencies (e.g., spanning between 200 Hz-5 kHz). A response of at least 3 second order sections of the digital filter is adjusted. A second input signal in the ANR signal flow path is processed using the generated set of parameters to generate an output signal for driving the electroacoustic transducer of the ANR headphone.

With respect to a noise reduction device using a speaker and a microphone corresponding to each seat in a vehicle to reduce a noise in each seat, the noise reduction device includes, a signal processing unit configured to generate a canceling sound that reduces a noise at an ear of an occupant in a predetermined seat by using an auxiliary filter, an operation setting unit configured to disable operations of a speaker and a microphone corresponding to each empty seat in the vehicle, and an auxiliary filter setting unit configured to change a setting value of the auxiliary filter used by the signal processing unit to generate the canceling sound in accordance with the number of occupants in seats other than the predetermined seat, the seats affecting the noise in the predetermined seat.

Adaptive filters output a cancellation sound from a speaker, a selector selects outputs of a plurality of auxiliary filters each corresponding to different positions, a subtractor subtracts the selected output from the output of the microphone and outputs the subtracted output to the adaptive filter as an error signal, and a position detection device detects a position of a head of a user. A transfer function estimated so that the error signal becomes 0 when noise is canceled at the corresponding position is preset in the auxiliary filter. When the auxiliary filter corresponding to the position close to the head of the user changes, the switching control unit stepwise increases the frequency with which the output of the auxiliary filter is selected by the selector to 100%.

A noise cancellation system for a noise cancellation enabled audio device comprises a first noise filter and a second noise filter, each being designed to process a noise signal, a combiner and an adaptation engine. The first noise filter has a first fixed frequency response matched to a high leakage condition of the audio device. The second noise filter has a second fixed frequency response matched to a low leakage condition of the audio device. The combiner is configured to provide a compensation signal based on a combination of an output of the first noise filter amplified with a first adjustable gain factor and an output of the second noise filter amplified with a second adjustable gain factor. The adaptation engine is configured to estimate a leakage condition of the audio device based on an error noise signal and to adjust at least one of the first and the second adjustable gain factors based on the estimated leakage condition.

Two subsystems, each including a microphone, a speaker, a canceling sound-generating adder, an error-computing adder, and two adaptive filters and two auxiliary filters that accept two noises as input, are provided in correspondence with two cancellation positions. Each canceling sound-generating adder adds together the outputs from the adaptive filters and outputs the result to the speaker of each subsystem. Each error-computing adder adds together the output from the microphone of the subsystem and the output from the auxiliary filter of the subsystem, and the result is treated as the error of the adaptive filters of each subsystem. A transfer function is learned in advance and set in each auxiliary filter such that each error computed by each error-computing adder becomes zero (0) when a transfer function in which each noise is canceled at each cancellation position in a predetermined standard acoustic environment is set in each adaptive filter.

According to an example embodiment, an apparatus for active cancellation of sound and vibration is provided, the apparatus including sound and vibration generation components for jointly producing vibration and sound under control of a driving signal provided as input thereto, the components being arranged inside a padding to generate mechanical vibration that is perceivable as a vibration and sound on at least one outer surface of the padding and to radiate a sound through the at least one outer surface of the padding, a feedback unit for providing feedback information that is indicative of acoustic energy of sound and vibration inside the padding, and a drivert for generating the driving signal in dependence of the feedback information so as to reduce energy of ambient sound and vibration induced inside the padding due to one or more external sources of sound and vibration.

A hearing protection and situational awareness system includes a wearable device, speakers, one or more beamformers, a microphone array, and a computation unit. The system generates a three-dimensional (3D) binaural sound for enhanced situational awareness; provides hearing protection by active noise cancelation; provides hearing enhancement by automatic gain control; and performs background noise reduction and cancelation. The system performs automated sound detection, identification, and localization, with automated voice assistance, and facilitates clear two-way communications. Each beamformer(s) outputs a sound track associated with a sound captured by the microphone array in a direction(s) of an acoustic beam pattern(s). The computation unit combines filtered sound tracks generated using head-related transfer function (HRTF) filters into left and right sound channels to drive the speaker(s) in left and right hearing members of the wearable device, respectively, thereby generating a 3D binaural sound including cues of the sound source directions.

According to an example embodiment, an apparatus for active cancellation of sound and vibration is provided, the apparatus including sound and vibration generation components for jointly producing vibration and sound under control of a driving signal provided as input thereto, the components being arranged inside a padding to generate mechanical vibration that is perceivable as a vibration and sound on at least one outer surface of the padding and to radiate a sound through the at least one outer surface of the padding, a feedback unit for providing feedback information that is indicative of acoustic energy of sound and vibration inside the padding, and a drivert for generating the driving signal in dependence of the feedback information so as to reduce energy of ambient sound and vibration induced inside the padding due to one or more external sources of sound and vibration.

A kit for attenuation of noise includes a noise source audio transducer, two ear pieces, and a control unit. The two ear pieces have respective resilient bodies that engage outer portions of ear canals of respective ears of a user while respective in-ear transducers of the two ear pieces are respectively positioned in inner portions of the ear canals. The respective in-ear transducers detect discrepancies (e.g., incomplete superpositioning) between the noise and the anti-noise. The respective in-ear transducers optionally detect respective secondary path effects in the ear canals. The noise source audio transducer detects noise generated by a noise source (e.g., snoring noise). The control unit configures an adaptive filter based at least in part on an error signal, and optionally based in part on secondary path effects. The control unit generates signals representative of anti-noise. The two ear pieces produce the anti-noise responsive to the signals. The two ear pieces produce masking noise with sound level that varies in direct correlation with sound level of the noise generated by the noise source.

A kit for attenuation of noise includes a noise source audio transducer, two ear pieces, and a control unit. The two ear pieces have respective resilient bodies that engage outer portions of ear canals of respective ears of a user while respective in-ear transducers of the two ear pieces are respectively positioned in inner portions of the ear canals. The respective in-ear transducers detect discrepancies (e.g., incomplete superpositioning) between the noise and the anti-noise. The respective in-ear transducers optionally detect respective secondary path effects in the ear canals. The noise source audio transducer detects noise generated by a noise source (e.g., snoring noise). The control unit configures an adaptive filter based at least in part on an error signal, and optionally based in part on secondary path effects. The control unit generates signals representative of anti-noise. The two ear pieces produce the anti-noise responsive to the signals. The two ear pieces produce masking noise with sound level that varies in direct correlation with sound level of the noise generated by the noise source.