Abstract: A user content audio signal is converted into sound that is delivered into an ear canal of a wearer of an in-ear speaker, while the in-ear speaker is sealing off the ear canal against ambient sound leakage. An acoustic or venting valve in the in-ear speaker is automatically signaled to open, so that sound inside the ear canal is allowed to travel out into an ambient environment through the valve, while activating conversion of an ambient content audio signal into sound for delivery into the ear canal. Both user content and ambient content are heard by the wearer. The ambient content audio signal is digitally processed so that certain frequency components have been gain adjusted, based on an equalization profile, so as to compensate for some of the insertion loss that is due to the in-ear speaker blocking the ear canal. Other embodiments are also described and claimed.

Abstract: 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.

Abstract: There is provided a hearing aid with a Receiver In The Ear speaker assembly comprising an connecting member with electric conductors connecting a connector at one end, and a receiver housing with a receiver at the opposite end. A microphone housing with a microphone is attached to the connecting member. Placed along the connecting member, the microphone housing with the microphone is separated by a distance from the receiver in the receiver housing, thus reducing acoustic or mechanical feedback problems. Especially, the microphone and connector may share one common housing.

Abstract: The disclosure relates to a hearing device comprising a housing accommodating an acoustic transducer inside an inner volume of the housing, the acoustic transducer having an oscillator element configured to generate sound waves, the housing accommodating the acoustic transducer inside an inner volume of the housing. The hearing device further comprises a sound outlet configured to release sound waves from the inner volume into an ear canal. The hearing device may also comprise a microphone configured to be acoustically coupled to the ear canal, and an active feedback control circuit configured to provide an active feedback control signal to modify the sound waves generated by the acoustic transducer.

Abstract: A speech enhancement apparatus is disclosed and comprises an adaptive noise cancellation circuit, a blending circuit, a noise suppressor and a control module. The ANC circuit filters a reference signal to generate a noise estimate and subtracts a noise estimate from a primary signal to generate a signal estimate based on a control signal. The blending circuit blends the primary signal and the signal estimate to produce a blended signal. The noise suppressor suppresses noise over the blended signal using a first trained model to generate an enhanced signal and a main spectral representation from a main microphone and M auxiliary spectral representations from M auxiliary microphones using (M+1) second trained models to generate a main score and M auxiliary scores. The ANC circuit, the noise suppressor and the trained models are well combined to maximize the performance of the speech enhancement apparatus.

Abstract: Embodiments of active noise control (ANC) headphones and operating methods thereof are disclosed herein. In one example, a headphone for ANC includes a speaker, an internal microphone, a processor, and a filter function module. The speaker is configured to play an audio based on a first audio source signal. The internal microphone is configured to obtain a mixed audio signal comprising a noise signal and a second audio source signal based on the audio of interest played by the speaker. The processor is configured to determine a current system parameter of the ANC headphone based on the mixed audio signal at a first time point and determine a current parameter of a filter function module based on the current system parameter of the ANC headphone and pre-tested data. The filter function module is to perform ANC based on the determined current parameter of the filter function module.

Abstract: A noise cancellation enabled audio device, in particular a headphone, comprises a speaker which is arranged within the audio device and which has a preferential side for sound emission. The audio device further comprises a first cavity enclosing a first volume of air, where the first cavity is arranged at the preferential side for sound emission of the speaker, and an error microphone which is arranged within a second cavity within the audio device. The first cavity comprises a first opening to the outside of the audio device and the second cavity comprises a second opening to the outside of the audio device. The first and the second opening are both arranged on a side of the audio device which is arranged to face an ear canal of a user. Furthermore, a noise cancellation system is provided.

Abstract: In general, in one aspect, a hearing aid has an ANR circuit and an ear tip that acoustically occludes the ear. Such a hearing aid provides greater gain to sounds than would be stable in the same hearing aid with a vented ear tip. The ear tip and the ANR circuit in combination attenuate sounds reaching the ear canal through the hearing aid to a first level. The hearing aid detects sounds arriving at a microphone, amplifies those sounds, and provides the amplified sounds to the ear canal at a second level and later in time than the same sounds arrive at the ear canal through the ear tip. The first level is at least 14 dB greater than the second level, such that the amplified sounds do not interact with the passive sounds to result in spectral combing.

Abstract: Various embodiments include a computer-implemented method comprising receiving an input signal representing an ambient auditory environment of a user, generating, from the input signal, a set of ambient audio signals that includes a first component signal and a second component signal, generating, based on the first component signal, a first inverse signal that is a polar inverse of the first component signal, removing the first component signal from the set of ambient audio signals, generating a first composite signal that includes at least the first inverse signal and the second component signal, and driving an audio output device to produce soundwaves based on the first composite signal.

Abstract: A ballistic helmet comprising a ballistic shell, wherein within the thickness of the ballistic shell, or inside the ballistic shell, there is provided one or more circuit layers forming a circuit, which circuit comprises a power bus and a data bus, and wherein one or more power connections and one or more data connections are provided on the inside and/or on an edge of the ballistic shell for providing power and data to/from one or more electrical devices through the circuit.

Abstract: A headphone earcup including a frame defining a cavity dimensioned to surround an ear of a user; a damping component coupled to the frame and encircling the cavity; a wrap component that covers the damping component and defines a continuous acoustic opening around the cavity to acoustically connect the cavity to the damping component; and a cosmetic component that covers the wrap component and the continuous acoustic opening.

Abstract: A noise sensor is disposed adjacent a speaker within an ear cup of a hearing protection device. The speaker is disposed within a speaker housing and the noise sensor is disposed within a sensor housing, the sensor housing coupled to the speaker housing such that the noise sensor and speaker remain adjacent one another. The noise sensor includes at least a microphone operably coupled to a printed circuit board. The sensor housing defines an axial bore such that the noise sensor can receive acoustic signals via the axial bore. The sensor housing can be coupled to the speaker housing such that the noise sensor is sealed therebetween and receives acoustic signals via a distal end of the axial bore opposite the speaker. A calibration tool can be disposed to the axial bore via the distal end for airtight calibration of the noise sensor.

Abstract: Aspects of the disclosure relate to using a display as a sound emitter and may relate to an electronic device including a display and for sound leak cancellation. A vibration sensor such as an accelerometer is physically coupled to the display and senses the display vibration to provide a signal representing actual acoustic output from the display. The electronic device includes a first actuator physically coupled to the display and configured to cause vibration of the display in response to a first audio signal. The electronic device further includes the vibration sensor configured to output a vibration sensor signal proportional to the vibration of the display. The electronic device further includes a second actuator physically coupled to a portion of the electronic device different from where the first actuator is physically coupled to the display and configured to cause vibration of the portion in response to a second audio signal.

Abstract: Various examples of the present invention relate to an apparatus and a method for removing noise from a reception signal and a transmission signal. A method for operating a sound system for removing noise from a reception signal and a transmission signal, according to an example of the present invention comprises the steps of: receiving power through a first path from another electronic device; receiving a plurality of signals including transmission signals from a plurality of microphones; generating first data by multiplexing the plurality of received signals on the basis of the received power; and transmitting, through the first path, the generated first data to the other device. In addition, other various examples are possible.

Abstract: An example method includes, at an electronic device: receiving an indication of a notification; in accordance with receiving the indication of the notification: obtaining one or more data streams from one or more sensors; determining, based on the one or more data streams, whether a user associated with the electronic device is speaking; and in accordance with a determination that the user is not speaking: causing an output associated with the notification to be provided.

Abstract: Various implementations include systems for processing audio signals. In particular implementations, a system for processing audio signals includes: a wearable audio device having a transducer and a communication system; and an accessory device configured to wirelessly communicate with the wearable audio device, the accessory device having a processor configured to process a source audio signal according to a method that includes: source separating the source audio signal; and providing a source separated audio signal to the wearable audio device for transduction.

Abstract: The present invention discloses a speaker module, comprising a housing and a speaker unit located in an inner cavity of the housing and dividing the inner cavity into a front acoustic cavity and a rear acoustic cavity separated from each other, wherein the housing is additionally provided with a pressure relief device configured to communicate the rear acoustic cavity with an external environment and implement an acoustic seal, the pressure relief device comprises a pressure relief hole extending through a thickness direction of the housing and provided with a gland on one side close to the rear acoustic cavity, and a pressure relief groove is disposed at a surface of the gland close to the pressure relief hole, one end of the pressure relief groove is connected with the pressure relief hole, the other end of the pressure relief groove is led out of an end of the gland, and the pressure relief groove and the pressure relief hole together make up a pressure relief passage of the rear acoustic cavity.

Abstract: A system and method for accurately estimating engine noise at a virtual microphone location, such as an occupant's ear position, in an acoustic space in order to enhance performance of an Engine Order Cancellation (EOC) system is provided. A set of weights and transfer functions that are dependent on various vehicle parameters, such as frequency, load, and speed, may be employed to estimate noise at a position where there are no physical microphones present. The accurate estimation of engine noise at virtual location, such as an occupant's ear position, may be achieved using a frequency dependent weighted sum of filtered and unfiltered error signals measured at microphones mounted at various locations inside an acoustic space, such as a vehicle cabin, which may not be located near virtual location.

Abstract: The present disclosure provides methods and systems for reducing noise induced in one or more components in a hearing aid. The present disclosure provides methods for reducing noise induced in telecoils.

Abstract: While a first wearable audio output component of a wearable audio output device is in a first position relative to a first ear of a user and a second wearable audio output component of the wearable audio output device is in the first position relative to a second ear, a computer system operates the wearable audio output device in a first mode. While doing so, the computer system detects a change in position of the first component from the first position to a second position; and, in response, while the second component is maintained in the first position, the computer system transitions the wearable audio output device from the first mode to a different, second mode that is a pass-through mode in which audio outputs provided via the wearable audio output device include pass-through audio components that include at least a portion of ambient sound from the physical environment.

Abstract: An audio system has an ambient sound enhancement function, in which an against-the-ear audio device having a speaker converts a digitally processed version of an input audio signal into sound. The input audio signal may be amplified where the amplification may be in accordance with a stored hearing profile of the user (personalized ambient sound enhancement.) The audio system also has an acoustic noise cancellation (ANC) function that may be combined in various ways with the sound enhancement function, and that may be responsive to voice activity detection. Other aspects are also described and claimed.

Abstract: A method for operating a hearing aid comprises: acquiring a sound signal; classifying the acquired sound signal with respect to predefined sound classes, wherein a raw class mixing weighting is determined, in which the sound signal is weighted with respect to the sound classes; processing the sound signal with at least one actuator, wherein the actuator processes the sound signal based on an actual actuator parameterization, wherein each sound class comprises a sound class actuator parameterization for each actuator, and the actual actuator parameterization for each actuator is generated by mixing the sound class actuator parameterization of the sound classes based on the raw class mixing weighting; and outputting the processed sound signal to be perceived by the user of the hearing aid.

Abstract: An earmuffs system for noise reduction including an external microphone used in combination with active noise cancellation technology for the reduction of wind or other noises typically experienced while riding a vehicle such as a motorcycle, snow machine or ATV, the earmuffs system including a first earmuff including a first speaker and a first microphone therein; a second earmuff electrically coupled to the first ear muff, the second ear muff including a second speaker and a second microphone therein; noise cancellation circuitry for receiving first sounds from the first microphone and the second microphone and processing the first sounds by in part canceling the first sounds to form a first sound output that is provided from the first speaker and the second speaker; a third microphone placed external to the first earmuff, the third microphone supplying second sounds for the first speaker to output as a second sound output without the second sounds undergoing noise cancellation processing; and a fourth micr

Abstract: A feedforward ambient noise reduction arrangement includes, within a housing, a loudspeaker device for directing sound energy into an ear of a listener. Disposed externally of the housing, and positioned to sense ambient noise on its way to the listener's ear, are plural microphone devices capable of converting the sensed ambient noise into electrical signals for application to the loudspeaker to generate an acoustic signal opposing the ambient noise. Importantly, the overall arrangement is such that the acoustic signal is generated by said loudspeaker means in substantial time alignment with the arrival of said ambient noise at the listener's ear.

Abstract: A method for on ear detection for a headphone, the method comprising: receiving a first microphone signal derived from an first microphone of the headphone and determining, from the first microphone signal, a first resonance frequency associated with an acoustic port of the first microphone, the first resonance frequency dependent on a first temperature at the first microphone; receiving a second microphone signal derived from an second microphone of the headphone and determining, from the second microphone signal, a second resonance frequency associated with an acoustic port of the second microphone, the second resonance frequency dependent on a second temperature at the second microphone.

Abstract: A headphone/mp3 player assembly for listening to audio from a plurality of audio sources includes a pair of headphones that can be worn on a listeners' head. A control circuit is coupled to the headphones and a media player is integrated into the headphones. The media player is electrically coupled to the control circuit. A radio tuner is coupled to the headphones for receiving FM and AM radio signals and the radio tuner is electrically coupled to the control circuit. A transceiver is coupled to the headphones and the transceiver is electrically coupled to the control circuit. The transceiver is configured can be placed in electrical communication with an electronic audio source for receiving an audio signal therefrom. A pair of speakers is each of the speakers is coupled to a respective one of the headphones and each of the speakers is electrically coupled to the control circuit.

Abstract: Provided is a hearing device including a housing configured to be at least partially inserted into an ear canal of a user, a vent that provides venting between an inner region of the ear canal and the ambient environment, an acoustic valve with a valve member configured to adjust the effective size of the vent, an actuator that actuates the valve member, and an acoustic output transducer acoustically coupled to the inner region of the ear canal and configured to generate a sound output according to an audio signal. The hearing device further includes a control unit operatively connected to the actuator and the acoustic output transducer and configured to control the audio signal supplied to the acoustic output transducer such that the sound output is modified during adjustment of the valve member.

Abstract: An audio device for reducing pop noise is adapted to compensate for a direct current (DC) offset of an audio source signal and output the audio source signal to an audio playing device. The audio device includes a linear operation circuit, an adder, a digital-to-analog circuit, and an amplification circuit. The digital-to-analog circuit is coupled between the adder and the amplification circuit. The linear operation circuit generates a DC offset value based on a linear equation, a temperature parameter, a slope parameter, and a constant. The adder is configured to process an input signal and the DC offset value to generate a calibration signal. The digital-to-analog circuit is configured to convert a calibration signal in a digital form to a calibration signal in an analog form. The amplification circuit is configured to process the calibration signal in the analog form to output the audio source signal.

Abstract: A speaker box includes an upper shell and a lower shell that define a receiving space, and a speaker unit received in the receiving space and dividing the receiving space into front and rear cavities. The speaker unit includes a diaphragm spaced apart from the upper shell to form a front acoustic cavity. The upper shell is formed with a sound transmitting channel communicating the front acoustic cavity with the outside. The upper shell includes a top wall, and a support wall extending from the top wall towards the lower shell. The speaker box further includes a partition wall extending from the top wall towards the lower shell, and a cover plate extending from the partition wall towards the support wall. The partition wall, the cover plate and the support wall define at least two resonant cavities spaced apart from each other and in communication with the front cavity.

Abstract: Example embodiments may include one or more of receiving an electrical sound emission signal from a sound controller, interrupting reception of the electrical sound emission signal, by a sound emission interruption circuit connected to a sound emitter, and receiving an electrical ambient sound signal via a sound detection circuit, based on ambient sound sensed by the sound emitter when the reception of the electrical sound emission signal is interrupted by the sound emission interruption circuit.

Abstract: A voice aware audio system and a method for a user wearing a headset to be aware of an outer sound environment while listening to music or any other audio source. An adjustable sound awareness zone gives the user the flexibility to avoid hearing far distant voices. The outer sound can be analyzed in a frequency domain to select an oscillating frequency candidate and in a time domain to determine if the oscillating frequency candidate is the signal of interest. If the signal directed to the outer sound is determined to be a signal of interest the outer sound is mixed with audio from the audio source.

Abstract: An audio codec system includes an audio driver path coupled to a first node of the audio codec system. A first terminal of a sense resistor external to the audio codec system is coupled to the first node and a second terminal of the sense resistor is coupled to an auxiliary device load. The audio codec system includes a second path having a first bias circuit, a second bias circuit and an off-chip voltage reference. The first bias circuit is coupled to a second node of the audio codec system. The second bias circuit is coupled to a third node of the audio codec system. The off-chip voltage reference is associated with the auxiliary device load coupled between the first bias circuit and the second bias circuit.

Abstract: Technology described in this document can be embodied in an active noise reduction (ANR) headset earpiece that includes a first microphone disposed on the ANR headset earpiece such that the first microphone is configured to capture a first input signal representing noise traversing a first noise pathway through the ANR headset earpiece, and a second microphone disposed on the ANR headset earpiece such that the second microphone is configured to capture a second input signal representing noise traversing a second noise pathway through the ANR headset earpiece. Positions of the first microphone and the second microphone on the ANR headset earpiece are configured such that a first target level of coherence is achieved at multiple frequencies, the first target level of coherence at a particular frequency representing a fraction of an output signal that can be suppressed using the first input signal and the second input signal together.

Abstract: In a system and method for voice activity detection (VAD) including: obtaining audio frames from a multi-microphone array; calculating steered response power (SRP) values of the audio frames; calculating entropy levels based on the SRP values; detecting a sequence of audio frames in which the entropy levels are substantially constant across the sequence of frames and denoting an entropy level of the sequence as a background entropy; identifying an incoming audio frame as containing voice activity if the difference between a level of entropy of the current audio frame and the background entropy is larger than a first threshold, and as not containing voice activity otherwise.

Abstract: The invention relates to the field of electronic technology, and more particularly, to a microphone structure. A MEMS (Micro-Electro-Mechanical System)-based bone conduction sensor comprises: a closed cavity within which a uniaxial or biaxial accelerometer sensor is arranged to be adjacent to bones of a human ear; an ASIC (application-specific integrated circuit) processing chip coupled to the uniaxial or biaxial accelerometer sensor, the ASIC processing chip being provided with an output end for a vibration signal. By adopting the above-mentioned technical solution, a bone conduction sensor with a closed cavity is provided in the present invention. Furthermore, a uniaxial or biaxial accelerometer sensor and an ASIC processing chip are arranged inside the closed cavity. In this way, the production costs are reduced, and interference of the sensor caused by ambient environment is reduced.

Abstract: The accuracy of ear authentication is ensured over a range from an audible range to a non-audible range. An earphone includes a sound emitting unit, a sound collecting unit, a housing containing the sound emitting unit and the sound collecting unit, a sound hole formed inside the housing, the sound hole being configured to propagate an emitted sound to a predetermined direction and propagate a sound coming from the predetermined direction to the sound collecting unit, and an ear pad covering at least a part of the sound hole, in which an ear-pad side end face is configured so as not to project beyond a sound-hole side end face at least in the predetermined direction, the ear-pad side end face being an end face of the ear pad, the sound-hole side end face being an end face of the sound hole in the predetermined direction.

Abstract: An earpiece includes a feed-forward microphone coupled to the environment outside the headphones, a feedback microphone coupled to an ear canal of a user when the earpiece is in use, a speaker coupled to the ear canal of the user when the earpiece is in use, a digital signal processor implementing feed-forward and feedback noise compensation filters between the respective microphones and the speaker, and a memory storing an ordered sequence of sets of filters for use by the digital signal processor. Each of the sets of filters includes a feed-forward filter that provides a different frequency-dependent amount of sound pass-through or cancellation, which in combination with residual ambient sound reaching the ear results in a total insertion gain at the ear of a user.

Abstract: [Object] To shorten a time until an effect is obtained after start of an adaptive process mode on an ambient sound. [Solution] Provided is a signal processing device including: a noise cancellation processing unit configured to generate a noise cancellation signal on the basis of a collected ambient sound; a signal processing unit configured to generate an ambient sound adapted signal by performing dynamic analysis related to a feature of the ambient sound and filtering the ambient sound; and a control unit configured to control a plurality of modes related to signal processing. The plurality of modes includes a first mode in which acoustic reproduction based on the noise cancellation signal is performed and a second mode in which acoustic reproduction based on the noise cancellation signal and the ambient sound adapted signal is performed, and the signal processing unit continues the dynamic analysis even in the first mode.

Abstract: A method of equalising sound in a headset comprising an internal microphone configured to generate a first audio signal, an external microphone configured to generate a second audio signal, a speaker, and one or more processors coupled between the speaker, the external microphone, and the internal microphone, the method comprising: while the headset is worn by a user: determining a first audio transfer function between the first audio signal and the second audio signal in the presence of sound at the external microphone; and determining a second audio transfer function between a speaker input signal and the first audio signal with the speaker being driven by the speaker input signal; determining an electrical transfer function of the one or more processors; determining a closed-ear transfer function based on the first audio transfer function, the second audio transfer function and the electrical transfer function; and equalising the first audio signal based on a comparison between the closed-ear transfer func

Abstract: An information processing apparatus, an information processing method, and a program, which make it possible for a user to listen to an audio signal more appropriately, are provided. An information processing apparatus, including: behavior recognition unit configured to recognize behavior of a user on a basis of sensing information of at least one of the user and an environment; a processing controller configured to control, on a basis of the recognized behavior of the user, signal processing with respect to at least one of an audio signal listened to by the user, a noise reduction signal, and an external sound monitor signal; and a signal processing unit configured to execute the signal processing.

Abstract: Provided is an active noise cancellation (ANC) method applied for an ANC headphone. The ANC method includes: in a channel estimation mode, estimating a plurality of environment channels by generating, transmitting and capturing a training signal; in the channel estimation mode, tuning a plurality of ANC filters based on the estimated plurality of environment channels; and in a normal mode, performing ANC on an input signal based on the plurality of ANC filters.

Abstract: A signal processor comprising: an input terminal, configured to receive an input-signal; a voicing-terminal, configured to receive a voicing-signal representative of a voiced speech component of the input-signal; an output terminal; a delay block, configured to receive the input-signal and provide a filter-input-signal as a delayed representation of the input-signal; a filter block, configured to: receive the filter-input-signal; and provide a noise-estimate-signal by filtering the filter-input-signal; a combiner block, configured to: receive a combiner-input-signal representative of the input-signal; receive the noise-estimate-signal; and combine the combiner-input-signal with the noise-estimate-signal to provide an output-signal to the output terminal; and a filter-control-block, configured to: receive the voicing-signal; receive signalling representative of the input-signal; and set filter coefficients of the filter block in accordance with the voicing-signal and the input-signal.

Abstract: Various embodiments provide dynamic reconfiguration of a connectivity configuration associated with a wireless networking device. The wireless networking device maintains multiple wireless connections with multiple user devices using a combination of beam-formed wireless signals and omnidirectional wireless signals. The wireless network device generates a list of connected or associated user devices that are capable of beam-formed wireless communications, and obtains metrics for each respective user device. The wireless networking device prioritizes the list based upon the respective metrics, and determines whether a current connectivity configuration differs from the prioritization. Responsive to determining a difference, the wireless networking device can dynamically reconfigure the connectivity configuration by modifying a connection type associated with at least one user device.

Abstract: An audio system presented herein includes a transducer array, sensor array, and a controller. The controller control tactile content imparted to a user via actuation of at least one transducer in the transducer array while presenting audio content to the user. The transducer array presents the audio content with the tactile content to the user. The audio system can be part of a headset.

Abstract: In one aspect a method that includes receiving an input signal captured by one or more first sensors associated with an active noise reduction (ANR) device, and processing the input signal using a first filter disposed in an ANR signal path to generate a first signal for an acoustic transducer of the ANR device. The input signal is processed in a pass-through signal path disposed in parallel with the ANR signal path to generate a second signal for the acoustic transducer, wherein the pass-through signal path allows a portion of the input signal to pass through to the acoustic transducer in accordance with a variable gain. One or more second sensors detect an existence of a condition likely to cause instability in the pass-through signal path, and in response, the variable gain is adjusted. A driver signal for the acoustic transducer is generated using an output based on the adjusted gain.

Abstract: The earphone (1) is adapted to be arranged in an operating position at a first ear (5) of a user (4) and, in the operating position, provide a first acoustic output signal (SO) to the first ear (5). The earphone has a first input unit (31) adapted to receive a first audio input signal (SI); a first noise cancellation signal path (37) with a first microphone (26) and a first noise cancellation filter (32), wherein the first microphone (26) is arranged to receive ambient sound (SA) from ambient space (7) with the earphone in the operating position and is adapted to provide a corresponding first reference signal (SR), and wherein the first noise cancellation filter (32) is adapted to apply a first transfer function (H) to the first reference signal (SR) to provide a first noise cancellation signal (SC).

Abstract: An audio system for a wearable device dynamically updates acoustic transfer functions. The audio system is configured to estimate a direction of arrival (DoA) of each sound source detected by a microphone array relative to a position of the wearable device within a local area. The audio system may track the movement of each sound source. The audio system may form a beam in the direction of each sound source. The audio system may identify and classify each sound source based on the sound source properties. Based on the DoA estimates, the movement tracking, and the beamforming, the audio system generates or updates the acoustic transfer functions for the sound sources.

Abstract: A circuit having a dynamically adjustable common mode rejection ratio. The circuit has a high common mode rejection ratio without the need for input transformers. The circuit's ability to adjust the circuit's common mode rejection ratio is enhanced by the circuit's high input impedance. The circuit includes first and second input terminals, and output terminals. A positive leg runs from the first input terminal to the first output terminal, the positive leg including a resistor, and a negative leg runs from an input terminal to an output terminal. The digital signal processor controls a potentiometer on one of the legs to dynamically adjust the common mode rejection ratio of the circuit.

Abstract: An active noise control device includes: a reference signal source that outputs a reference signal having a correlation with noise; a reference signal input unit configured to receive the reference signal output from the reference signal source; a compressor that compresses the reference signal and outputs a compressed signal of the reference signal when an amplitude of the reference signal received by the reference signal input unit is greater than or equal to a threshold; and an adaptive filter unit configured to generate a canceling signal having a phase opposite to a phase of the compressed signal by multiplying the compressed signal using an adaptive filter having a coefficient that is updated successively. The coefficient of the adaptive filter is updated using a step size parameter for determining an amount of updating the coefficient of the adaptive filter based on a change in the amplitude of the reference signal.

Abstract: Digital audio signal processing techniques used to provide an acoustic transparency function in a pair of headphones. A number of transparency filters can be computed at once, using optimization techniques or using a closed form solution, that are based on multiple re-seatings of the headphones and that are as a result robust for a population of wearers. In another embodiment, a transparency hearing filter of a headphone is computed by an adaptive system that takes into consideration the changing acoustic to electrical path between an earpiece speaker and an interior microphone of that headphone while worn by a user. Other embodiments are also described and claimed.