A method for auralizing a multi-microphone device. Path information for one or more sound paths using dimensions and room reflection coefficients of a simulated room for one of a plurality of microphones included in a multi-microphone device is determined. An array-related transfer functions (ARTFs) for the one of the plurality of microphones is retrieved. The auralized impulse response for the one of the plurality of microphones is generated based at least on the retrieved ARTFs and the determined path information.

Implementations can detect respective audio data that captures an acoustic event at multiple assistant devices in an ecosystem that includes a plurality of assistant devices, process the respective audio data locally at each of the multiple assistant devices to generate respective measures that are associated with the acoustic event using respective event detection models, process the respective measures to determine whether the detected acoustic event is an actual acoustic event, and cause an action associated with the actional acoustic event to be performed in response to determining that the detected acoustic event is the actual acoustic event. In some implementations, the multiple assistant devices that detected the respective audio data are anticipated to detect the respective audio data that captures the actual acoustic event based on a plurality of historical acoustic events being detected at each of the multiple assistant devices.

Described embodiments generally relate to a signal processing device for on ear detection for an earbud. The device comprises a first microphone input for receiving a microphone signal from a first microphone, the first microphone being configured to be positioned within an ear of a user when the earbud is being worn; 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 earbud is being worn; a signal generator configured to generate a signal for acoustic playback from a speaker configured to be positioned within the earbud; and a processor. The processor is configured to receive at least one first microphone signal from each of the first microphone input and the second microphone input, and compare the first microphone signals to determine the on ear status of the earbud; determine that the on ear status of the earbud cannot be sufficiently determined, generate a signal for acoustic playback from the speaker, receive a second microphone signal from the first microphone input, and compare the second microphone signal to the generated signal to determine the on ear status of the earbud.

The disclosure relates to a system, comprising a first circuit board comprising a control circuitry configured to control a beamforming array of microphones, and multiple second circuit boards attached to the first circuit board, each one of the multiple second circuit boards mounting a microphone of the array of microphones.

A method and system for compensating a frequency response of a microphone array are provided. The method includes: multiple microphones in a microphone array respectively receiving a compensation signal sent from a calibration speaker and outputting multiple output signals respectively; determining a uniform frequency response of the multiple microphones based on the multiple output signals; calculating a compensation gain for each of the multiple microphones according to the uniform frequency response; and storing the calculated compensation gain of each microphone.

Described embodiments generally relate to a signal processing device for on ear detection for an earbud. The device comprises a first microphone input for receiving a microphone signal from a first microphone, the first microphone being configured to be positioned within an ear of a user when the earbud is being worn; 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 earbud is being worn; a signal generator configured to generate a signal for acoustic playback from a speaker configured to be positioned within the earbud; and a processor. The processor is configured to receive at least one first microphone signal from each of the first microphone input and the second microphone input, and compare the first microphone signals to determine the on ear status of the earbud; determine that the on ear status of the earbud cannot be sufficiently determined, generate a signal for acoustic playback from the speaker, receive a second microphone signal from the first microphone input, and compare the second microphone signal to the generated signal to determine the on ear status of the earbud.

Techniques are described for reducing sensitivity to non-acoustic stimuli. In some embodiments, differential beamforming is applied to microphone signals generated based on responses of microphones to an acoustic stimulus and a non-acoustic stimulus. Compensated signals can be generated based on the microphone signals such that the compensated signals are in phase with respect to the acoustic stimulus. The non-acoustic stimulus is detectable by comparing a first signal to a second signal to determine that one signal has a greater instantaneous magnitude. The first signal can be a beamformed signal or signal derived therefrom, and the second signal can be an average of the compensated signals or signal derived therefrom. An output audio signal can be generated by switching or cross fading between the beamformed signal and a noise-reduced signal such that a contribution of the noise-reduced signal is increased and a contribution of the beamformed signal is decreased.

Techniques are described for detecting and correcting mismatched microphone sensitivities in a microphone array without knowledge of the acoustic excitation source(s). Mismatch is detectable based on time and/or frequency domain analysis of each microphone's long term exposure to a real-world sound field that includes an acoustic source and a non-acoustic source, and is corrected by adjusting the amount of amplification applied to at least one microphone signal. In the time domain, sensitivity matching can be performed by using an average of all microphone signals as a reference signal. In some embodiments, the reference signal is the root mean square of the average. Alternatively, a single microphone can be selected as a reference. In some embodiments, sensitivity mismatch is detected and corrected at specific frequencies based on comparing frequency components of amplified microphone signals. Sensitivity matching can be repeated to ensure that the microphones remain sensitivity-matched over time.

Embodiments of wireless audio systems and methods for wirelessly communicating audio are disclosed herein. In one example, a method for generating a 3D audio representation of an audio is disclosed. The method includes collecting, by a first wireless headphone, a first audio signal at a first audio clock and generating, by the first wireless headphone, a first counting signal by counting cycles according to a first local clock of the first wireless headphone. The method also includes generating, by the first wireless headphone, a second synchronizing signal based on recording a value of the first counting signal and retrieving, by the first wireless headphone, a portion of the first audio signal by direct memory access (DMA). The method yet includes receiving, by a second wireless headphone, a wireless signal from the first wireless headphone, indicating the first local clock and synchronizing, by the second wireless headphone, a second local clock of the second wireless headphone with the first local clock based on the wireless signal. The method further includes collecting, by the second wireless headphone, a second audio signal at a second audio clock and generating, by the second wireless headphone, a second synchronizing signal based on a local clock of the second wireless headphone. The method yet includes retrieving, by the second wireless headphone, a portion of the first audio signal by DMA and generating, by a user equipment, the 3D audio representation of the audio based on the first and the second audio signals and the first and the second synchronizing signals.

Microphone capsules for condenser or electret microphones often exhibit individual deviations from a desired ideal behavior, e.g. the frequency response and phase response. Particularly if a plurality of microphone capsules are interconnected to form a microphone array, suitable microphone capsules must be found in a selection process. Some of these deviations can be corrected electronically, e.g. by filtering with a corresponding filter that is individually adapted. An improved microphone capsule, with which an automatic selection and automatic assembly of circuit boards with microphone capsules is facilitated, comprises an electrostatic sound transducer, an amplifier element that outputs an amplified output signal of the electrostatic sound transducer, and at least one electronic memory element. Data obtained by a measurement and relating to the individual frequency response or phase response of the respective microphone capsule can be stored therein. The data can be read out during manufacturing and during operation, which enables automatic sorting of the capsules during production and automatic calibration of the target circuit in operation.