An acoustic element includes a nanovoided polymer layer having a first nanovoid topology in an unactuated state and a second nanovoid topology different than the first nanovoid topology in an actuated state. Capacitive actuation of the nanovoided polymer layer, for instance, can be used to reversibly control the size and shape of the nanovoids within the polymer layer and hence tune its sound damping characteristics or sound transduction behavior, e.g., during operation of the acoustic element. An acoustic element may be configured for passive or active sound attenuation. Various other apparatuses, systems, materials, and methods are also disclosed.

Detecting a divergence in an adaptive system includes the steps of determining a power of a component of an error signal at a first frequency, the component being correlated to a noise-cancellation signal, the noise-cancellation signal being produced by an adaptive filter and being configured to cancel noise within a predetermined volume when transduced into acoustic signal, wherein the error signal represents a magnitude of a residual noise within the predetermined volume; determining a time gradient of the power of the component of the error signal; and comparing a metric to a threshold, wherein the metric is based, at least in part, on a value of the time gradient of the power of the component of the error signal over a period of time.

A method and system for noise cancellation is disclosed. In one embodiment, the method may include receiving, from a first sensor, a first signal indicative of a noise generated by an equipment. The first sensor may be configured to generate the first signal indicative of the noise generated by the equipment. The first sensor may be positioned in proximity to the equipment. The method may further include generating a noise cancellation signal based on the first signal and triggering a speaker to generate a sound corresponding to the noise cancellation signal, wherein the speaker is positioned in proximity to the equipment.

An active noise reduction system includes a substrate, a number of capacitors mounted on the substrate, a noise sensor mounted on the substrate and used to collect a noise signal around the noise sensor, an actuator mounted on the substrate and used to generate vibrations, and a controller mounted on the substrate and electrically coupled to the noise sensor and the actuator. The controller is used to obtain the noise signal collected by the noise sensor and generate a control signal according to the noise signal to the actuator to control the actuator to generate vibrations having a same frequency and opposite phase as the noise signal to cancel out the vibrations generated by the plurality of capacitors and the vibrations of the substrate caused by the vibrations generated by the plurality of capacitors. An electronic device and an active noise reduction method are also provided.

A system for actively mitigating a buffeting noise in an occupant compartment of a vehicle when the vehicle is moving. The system is configured to determine an estimated effective volume of the occupant compartment, and to determine if a single window of the vehicle occupant compartment is open. Responsive to a determination that a single window of the vehicle occupant compartment is open, and using the estimated effective volume of the occupant compartment, an estimated buffeting noise frequency is determined. Responsive to the estimated buffeting noise frequency, the system determines characteristics of a sound configured to cancel a buffeting noise generated inside the occupant compartment while the vehicle is moving. The system may then control operation of a noise cancelling signal generating system to generate the sound having characteristics configured to cancel the buffeting noise inside the occupant compartment.

An apparatus, method and computer program for controlling audio output is disclosed. The apparatus may comprise means for receiving data from one or more sensors representing one or more motion characteristics of a user and determining, based on the received data, one or more time instances associated with a sound event. The apparatus may also comprise means for controlling an active hear-through system of a wearable audio output device so as to temporarily modify, at a time of the one or more time instances, sound received by one or more input transducers associated with the active hear-through system that are output to an output transducer associated with the active hear-through system.

An active noise reduction system includes a reference signal generator configured to generate a reference signal, a canceling sound generator configured to generate a canceling sound, an error detector configured to detect an error between a noise and the canceling sound and generate an error signal corresponding to the error, and a controller configured to control the canceling sound generator based on the reference signal and the error signal, wherein the controller is configured to update an estimation value of acoustic characteristics in an internal space of a mobile body based on the reference signal and the error signal, estimate a head position of an occupant in the internal space based on the updated estimation value of the acoustic characteristics, and update a control filter based on the estimated head position of the occupant, the control filter being a filter for controlling the canceling sound generator.

Disclosed herein are a speaker device having a built-in microphone and a noise cancellation method using the same. The speaker device having the built-in microphone includes a microphone module picking up sound from a medium to generate a sound pickup signal, a speaker driver transmitting vibration corresponding to a reverse-phase signal of the sound pickup signal to tire medium, and a controller receiving the sound pickup signal from the microphone module, generating the reverse-phase signal of the sound pickup signal, and transmitting the reverse-phase signal to the speaker driver.

Embodiments generally relate to a signal processing device for on ear detection for a headset. The device comprises a first microphone input for receiving a microphone signal from a first microphone, the first microphone being configured to be positioned inside an ear of a user when the user is wearing the headset; a second microphone input for receiving a microphone signal from a second microphone, the second microphone being configured to be positioned outside the ear of the user when the user is wearing the headset; and a processor. The processor is configured to receive microphone signals from each of the first microphone input and the second microphone input; pass the microphone signals through a first filter to remove low frequency components, producing first filtered microphone signals; combine the first filtered microphone signals to determine a first on ear status metric; pass the microphone signals through a second filter to remove high frequency components, producing second filtered microphone signals; combine the second filtered microphone signals to determine a second on ear status metric; and combine the first on ear status metric with the second on ear status metric to determine the on ear status of the headset.

Embodiments generally relate to a signal processing device for on ear detection for a headset. The device comprises a first microphone input for receiving a microphone signal from a first microphone, the first microphone being configured to be positioned inside an ear of a user when the user is wearing the headset; a second microphone input for receiving a microphone signal from a second microphone, the second microphone being configured to be positioned outside the ear of the user when the user is wearing the headset; and a processor. The processor is configured to receive microphone signals from each of the first microphone input and the second microphone input; pass the microphone signals through a first filter to remove low frequency components, producing first filtered microphone signals; combine the first filtered microphone signals to determine a first on ear status metric; pass the microphone signals through a second filter to remove high frequency components, producing second filtered microphone signals; combine the second filtered microphone signals to determine a second on ear status metric; and combine the first on ear status metric with the second on ear status metric to determine the on ear status of the headset.