A digital circuit arrangement for an ambient noise-reduction system affording a higher degree of noise reduction than has hitherto been possible. The arrangement converts the analog signals into N-bit digital signals at sample rate f.sub.0, and then subjects the converted signals to digital filtering. The value of N in some embodiments is 1 but, in any event, is no greater than 8, and f.sub.0 may be 64 times the Nyquist sampling rate but, in any event, is substantially greater than the Nyquist sampling rate. This permits digital processing to be used without incurring group delay problems that rule out the use of conventional digital processing in this context. Furthermore, adjustment of the group delay can readily be achieved, in units of a fraction of a micro-second, providing the ability to fine tune the group delay for feed forward applications.

Systems and methods are provided an audio signal enhancement system that attenuates platform fan noise. Fan noise is a common type of self-noise in laptops and other devices, and fan noise can significantly degrade the quality of audio captured by built-in microphones. A neural network model is provided that enhances microphone Signal-to-Noise Ratio (SNR) and Signal-to-Distortion-plus-Noise Ratio (SDNR). The systems and methods also reduce algorithmic latency. The model architecture includes a Recurrent Neural Network, and a custom Gated Recurrent Unit layer is provided that uses fewer unique matrix weights and fewer biases and has fewer compute operations using fewer parameters. A platform self-noise suppression system is provided that eliminates low-amplitude platform self-noise signals. The model can predict when the platform fan is active, and remove the platform noise. In some examples, when the model predicts that the platform fan is not active, the model focuses on removing microphone self-noise.

Described herein are methods and systems for a vehicle system which provide inbuilt road noise cancellation in the vehicle. In one or more embodiments, a method for road noise cancellation comprises using a head-tracking device to monitor an occupant ear position, capturing airborne noise using a feedforward microphone and a headrest microphone of a zone in which the occupant ear is positioned, updating acoustic path information according to the occupant ear position(s) and speaker position(s) within the zone, generating a noise cancellation signal using sampling rate greater than 2 kHz, and outputting the noise cancellation signal via a headrest speaker located near the zone in which the occupant ear is positioned to at least partially reduce a road noise sound level in the zone.

A method and a device for a remote active noise control (ANC) of a vehicle are provided. The method includes receiving one or more local signals from a vehicle, wherein each local signal includes a reference signal, a noise control signal, an error signal, or a virtual error signal; updating the adaptive filters using the one or more local signals; and transmitting the updated adaptive filter to the vehicle.

Various aspects include active noise reduction (ANR) headsets and methods of controlling such headsets. In some implementations, a headset includes: at least one electro-acoustic transducer; a power source for powering the at least one electro-acoustic transducer; and a control circuit configured to apply active noise reduction (ANR) to environmental sound using the at least one electro-acoustic transducer, sample voltage drops across the power source, and adjust a compressor threshold for the ANR based on the sampled voltage drops across the power source.

Various aspects include active noise reduction (ANR) headsets and methods of controlling such headsets. In some implementations, a headset includes: at least one electro-acoustic transducer; a power source for powering the at least one electro-acoustic transducer, and a control circuit configured to apply active noise reduction (ANR) to environmental sound using the at least one electro-acoustic transducer, sample voltage drops across the power source, and adjust a compressor threshold for the ANR based on the sampled voltage drops across the power source.

A speaker and a microphone may be disposed in separate devices, wherein each of the digital to analog converter that is driving the speaker and the analog to digital converter that drives the microphone are driven by separate clocks. The speaker may be instructed to send (e.g., output) a pilot signal dedicated to synchronization. The microphone may detect the pilot signal, convert it to a digital signal, and an echo canceller (and/or resampler device) may use the digital signal output by the microphone to synchronize the clocks driving the digital to analog converter associated with the speaker device and the analog to digital converter associated with the microphone device. One or more packets containing audio samples may be sent to the speaker and the echo canceller as well as one or more packets sent to the echo canceller from the microphone device may be used to determine clock error.