Patent ID: 6928172

Claim:
An automatic sound field correcting system in an audio system for supplying a plurality of input audio signals to a plurality of sound generators via a plurality of signal transmission lines, each of the plurality of signal transmission lines including a frequency divider having a plurality of frequency discriminators each having a frequency discriminating characteristic different in frequency band, a plurality of in-channel level adjustors corresponding to the respective frequency discriminators, for adjusting levels of respective signals that are discriminated by the frequency discriminators, a channel-to-channel level adjustor for adjusting levels of the audio signals, and a delay unit for adjusting delay times of the audio signals, whereby the input audio signals are supplied to the sound generator via the frequency dividers, the in-channel level adjustors, the channel-to-channel level adjustor, and the delay unit, said correcting system comprising: a noise generator for supplying a noise to the respective signal transmission lines independently in correcting a sound field; a detector for detecting reproduced sounds generated from the noise reproduced by the respective sound generators; an in-channel level corrector for correcting an adjusted amount of the plurality of in-channel level adjustors based on detection results of the detector, wherein the in-channel level corrector performs the correction of the adjusted amount of the plurality of in-channel level adjustors with respect to each sound generator; a channel-to-channel level corrector for correcting an adjusted amount of the plurality of channel-to-channel level adjustors based on the detection results of the detector; and a phase characteristic corrector for calculating phase characteristics of the reproduced sounds reproduced by the sound generator based on the detection results of the detector and also correcting delay times of the delay unit based on calculated phase characteristics, wherein the channel-to-channel level corrector corrects the adjusted amount of the plurality of channel-to-channel level adjustors on the basis of one data of the reproduced sounds having a minimum value with respect to the reproduced sounds, which is extracted through the in-channel level corrector of each sound generator.