Patent ID: 7885417

Claim:
An active noise tuning system for tuning an acoustic noise generated by a noise source, comprising: a sound sensor that detects audio at a listening location and provides a sensed signal indicative thereof; an audio signal source that provides a useful signal indicative of audio; a noise signal source that generates an electrical noise signal that corresponds to the acoustic noise of the noise source; a first adaptive filter that filters the electrical noise signal and is controlled by first adaptive filter coefficients, and provides a first adaptive filter output signal; a summer that sums the useful audio signal and the first adaptive filter output signal and provides a summed signal indicative thereof; a sound reproduction device that acoustically emits audio indicative of the summed signal in the listening location; and a second adaptive filter having second adaptive filter coefficients, which filters the useful signal and provides a second adaptive filter output signal indicative thereof, where the second adaptive filter has a transfer function that models the acoustic path between the sound reproduction device and the sound sensor; a second summer that receives the sensed signal and second adaptive filter output signal and provides a difference signal indicative of the difference there between; and a coefficient computational unit that receives the difference signal and provides the second adaptive filter coefficients.