| 摘要 |
PROBLEM TO BE SOLVED: To eliminate a standing wave in a trunk room and to output a sound with excellent quality into a car room. SOLUTION: A signal processing part 11 obtains a frequency band that the mode and the spatial sound pressure distribution of the largest standing wave generated in the trunk room TRR become clear when the sound is outputted from an audio sound reproducing speaker SP. Then, a speaker SPC1, a microphone MC1 /the speaker SPC2, the microphone MCN-1 are respectively arranged in the trunk room in which the spatial distribution coefficient of this mode becomes positive/negative. An adaptive signal processor 13 performs adaptive signal processing so that output signals of respective microphones become the same waveform to decide the coefficients of adaptive filters 13a-1 , 13a-2 . An audio signal is inputted to the reproducing speaker SP, and is inputted to a band-pass filter 12 becoming a pass-band equal to the frequency band, and the band-pass filter 12 inputs its output signal to the adaptive filters 13a-1 , 13a-2 , and the adaptive filters 13a-1 , 13a-2 input filter outputs to respective controlling speakers SPC1, SPC2. |
