Abstract: In a behavior identification method, surrounding sound is acquired, a feature value that is specified by a spectrum pattern included in spectrum information generated from sound made by a person performing a predetermined behavior is extracted from the sound acquired, the predetermined behavior is identified by the feature value, and information indicating the predetermined behavior identified is output.

Abstract: Various implementations include speaker systems. In one implementation, a self-powered speaker system includes: a first module, having: a processor; an audio signal and control connector coupled with the processor and enabling audio signal and control communication between the processor and another module in the speaker system; a dedicated power supply for the speaker system; a front end backup power supply; and a power connector coupled with the dedicated power supply and the front end backup power supply, the power connector enabling input power to the dedicated power supply and output power from the front end backup power supply.

Abstract: Embodiments of the present invention are directed to a system and method for demonstrating spatial performance of a demonstration speaker model to consumers in order to evaluate different speakers. The system and method comprise a microphone array for recording the output of the demonstration speaker model. The system and method comprise acoustic input samples for processing to an acoustic output and a processor for determining characteristics of each microphone recording, and processing an acoustic input sample and characteristics of each microphone recording corresponding to a selected demonstration speaker model. The system and method further comprise a reference speaker model for outputting an acoustic signal based on the result of the processing.

Abstract: Provided are an echo delay time estimation method and system thereof, wherein the echo delay time estimation method is executed by the echo delay time estimation system with the following steps: receiving a testing signal and a received signal and executing a time to frequency analysis to generate a testing signal spectrogram and a received signal spectrogram; respectively executing a characteristic signal dynamic detection calculation for the testing signal spectrogram and the received signal spectrogram to generate a testing signal characteristic dynamic vector and a received signal characteristic dynamic vector; executing a cross-correlated vector estimation for the testing signal characteristic dynamic vector and the received signal characteristic dynamic vector to generate a cross-correlated vector; and calculating an echo delay time according to the cross-correlated vector.

Abstract: An adaptive dynamic audio hum extractor eliminates line frequency hum components and associated higher harmonics from an audio signal. An audio signal containing line frequency hum can be processed by providing dynamically controlled notch filters at the fundamental line frequency and additional harmonic multiples of the fundamental frequency. The audio signal is detected to provide dynamic control of the depth of the notch filters. Alternatively, an audio signal containing hum can be processed by dividing the spectrum into at least two frequency bands, an unaltered high band combined with a dynamically processed low band. The adaptive dynamically controlled notch filters vary the depth of the notches in relation to the envelope or time averaged level of the bandwidth limited audio signal. This allows masking of the hum components with higher levels of audio, thereby providing transparency devoid of audio path notches.

Abstract: A system and method to prevent eavesdropping by a device. An anti-eavesdrop component is installed on the device. The anti-eavesdrop component is configured to actively prevent the device from capturing audio from the environment. In response to installing the anti-eavesdrop component, the device recognizes the anti-eavesdrop component as a primary audio input for the device. The anti-eavesdrop component then proceeds to block the device from capturing outside audio by injecting noise or otherwise interfering with the primary audio input.

Abstract: An acoustic transducer comprises a transducer substrate, and an aperture having a non-circular perimetral shape defined through the transducer substrate. A diaphragm is disposed on the transducer substrate and coupled to a surface of the transducer substrate via at least one diaphragm anchor such that a gap is defined between the diaphragm and the transducer substrate, and an outer periphery of the diaphragm extends radially outwards of a rim of the aperture such that a portion of the diaphragm overhangs the aperture.

Abstract: A driver circuit of a capacitive speaker is provided. Positive and negative power terminals of a first output stage circuit are respectively coupled to a first power source and a second power source. The first output stage circuit outputs a first voltage signal to a first terminal of a capacitive load of the capacitive speaker according to a first audio input signal, a voltage of the first power source and a voltage of the second power source. Positive and negative power terminals of a second output stage circuit are respectively coupled to the second power source and a third power source. The second output stage circuit outputs a second voltage signal to a second terminal of the capacitive load of the capacitive speaker according to a second audio input signal, a voltage of the second power source and a voltage of the third power source.

Abstract: Various aspects include active noise reduction (ANR) devices and approaches, one approach including: receiving an input signal representing audio captured by a feedforward microphone of an ANR headphone; receiving an error signal representing audio captured by an error measurement sensor; generating an anti-noise signal configured to reduce a noise signal over a frequency range; and applying a gain to at least one of the input signal or the anti-noise signal over the frequency range based on the error signal, where the gain is calculated by: filtering the anti-noise signal over the frequency range to generate a filtered feedforward signal, and filtering the error signal over the frequency range to generate a filtered error signal; estimating a feedforward path contribution to the error signal; and determining the gain based on a correlation between the filtered error signal and the filtered feedforward signal with the assigned feedforward path contribution to the error signal.

Abstract: In an embodiment, a method for shaping a PWM signal includes: receiving an input PWM signal; generating an output PWM signal based on the input PWM signal by: when the input PWM signal transitions with a first edge of the input PWM signal, transitioning the output PWM signal with a first edge of the output PWM signal; and when the input PWM signal transitions with a second edge before the first edge of the output PWM signal transitions, delaying a second edge of the output PWM signal based on the first edge of the output PWM signal.

Abstract: An apparatus of generating a sound of a vehicle includes a motor configured to generate a torque of a rotational component and a torque of a vibration component, based on a target driving current, a controller configured to generate the target current by synthesizing a first signal for generating the torque of the rotational component and a second signal for generating the torque of the vibration component, and determine the target driving current for driving the motor based on the target current, and a sound output device to generate a target sound due to the torque of the vibration component.

Abstract: A headphone driver is used to drive a headphone apparatus, which includes a first differential driver, a first positive output terminal, a first negative output terminal, and a second negative output terminal. The first positive output terminal is connected to the first terminal. A switch unit is disposed on a feedback path at the first negative output terminal and the second negative output terminal, to enable the first/second negative output terminal in feedback as a close loop to output to the third/fourth terminal and disable the second/first negative output terminal at a first/second operation state. The first differential driver includes a first positive voltage driving circuit, a first negative voltage driving circuit, and a second negative voltage driving circuit, respectively providing the first positive output terminal, the first negative output terminal, and the second negative output terminal.

Abstract: The invention discloses rendering sound field signals, such as Higher-Order Ambisonics (HOA), for arbitrary loudspeaker setups, where the rendering results in highly improved localization properties and is energy preserving. This is obtained by rendering an audio sound field representation for arbitrary spatial loudspeaker setups and/or by a a decoder that decodes based on a decode matrix (D). The decode matrix (D) is based on smoothing and scaling of a first decode matrix {circumflex over (D)} with smoothing coefficients. The first decode matrix {circumflex over (D)} is based on a mix matrix G and a mode matrix {tilde over (?)}, where the mix matrix G was determined based on L speakers and positions of a spherical modelling grid related to a HOA order N, and the mode matrix {tilde over (?)} was determined based on the spherical modelling grid and the HOA order N.

Abstract: Systems and methods include a digital control module that receives and processes audio data for output through a loudspeaker. An analog block receives the audio data and the power control signal and amplifies the audio data for output. A first processing path includes a buffer to delay the audio data, a first component to combine the buffered audio data and anti-noise. A second processing path includes an absolute value block to receive the audio data and an envelope detector to receive the absolute value data and generate a maximum value for the envelope. An anti-noise path includes an absolute value block configured to determine an anti-noise absolute value which is combined with the absolute value anti-noise data. A power generator receives the output from the envelope detector and updates a power level to approximate a minimum powered needed to process the audio signal.

Abstract: This application provides an audio rendering method, including: obtaining a to-be-rendered BRIR signal, where an elevation angle corresponding to the to-be-rendered BRIR signal is 0 degrees; obtaining a direct sound signal based on the to-be-rendered BRIR signal; correcting, based on a target elevation angle, a frequency-domain signal corresponding to the direct sound signal, to obtain a frequency-domain signal corresponding to the target elevation angle; obtaining a time-domain signal based on the frequency-domain signal of the target elevation angle; and superposing the time-domain signal on a signal that is in the to-be-rendered BRIR signal and that is in a second time period after a first time period, to obtain a BRIR signal of the target elevation angle.

Abstract: A system and method to encode and decode multiple audio signals to provide independent control of the audio signals is provided. A host device may encode the audio signals to enable a complete separation of the constituent audio signals when the mixed stream is decoded on a playback device. The gains of the audio signals may be independently controlled before they are mixed to increase the intelligibility of one audio signal relative to another audio signal at the playback device. The ability to separate the constituent audio signals from the mixed signals at the playback device allows the processing operations performed on the constituent audio signals and the associated path latencies to be independently chosen. In addition, in applications where the mixed stream is transmitted from a single host device to multiple playback devices, the constituent audio signals may be selectively masked on a playback device to increase user privacy.

Abstract: A system that reproduces an output signal including dynamic range enhancement (DRE) reduces audible artifacts generated by changes in operating range of the dynamic range enhancement (DRE) when the output signal includes an adaptive noise canceling (ANC) component. A first detection circuit determines an input signal amplitude and a second detection circuit determines a measure of an amplitude of a noise canceling component of the input signal. A control circuit determines whether the amplitude of the noise canceling component is significant with respect to the input signal amplitude and controls characteristics of a dynamic range enhancer to override a default behavior of the dynamic range enhancer if the amplitude of the noise-canceling component is significant with respect to the input signal amplitude. The characteristics may include rise/fall times of a gain control of the dynamic range enhancer and may be controlled in multiple separate frequency bands.

Abstract: A method of regulating power supply to a speaker and a system for regulating power supply to a speaker comprising a generating of a low frequency signal output to the speaker, sensing a current and a voltage of the speaker after the low frequency signal is output to the speaker, measuring an impedance of the speaker based on the current and voltage, determining a temperature of the speaker and comparing with a threshold value, and lowering a power supply to the speaker where the temperature is above the threshold value.

Abstract: An inspection device is provided, including a base, a circuit assembly, an electrocardiogram sensor, a diaphragm, an annular member, and a positioning member. The base has a top surface, a bottom surface, a guiding portion, an opening, and an accommodating space. The guiding portion is formed on the top surface, the opening is formed on the bottom surface, and the accommodating space is formed between the top surface and the bottom surface. The circuit assembly is disposed in the accommodating space, and has a first contact and a second contact. The electrocardiogram sensor is disposed on the bottom surface and electrically connected to the circuit assembly. The diaphragm covers the opening. The annular member is rotatably connected to the base and has a guiding member. The guiding member is slidably connected to the guiding portion. The positioning member is affixed to the annular member and has a contacting portion.

Abstract: The disclosure relates to microphone and other sensor assemblies having a transduction element and an integrated circuit. The integrated circuit includes a switched-capacitor delta-sigma analog-to-digital converter (ADC) including a first integrator stage having a switched-capacitor circuit and a first plurality of parallel amplifiers. A logic circuit coupled to the integrator circuit is configured to selectably disable a subset of enabled amplifiers of the first integrator stage during a first phase of operation and to re-enable the subset of disabled amplifiers during a second phase.