ACOUSTIC SIGNAL PROCESSING APPARATUS

PROBLEM TO BE SOLVED: To widen a range of expression of a reproduction sound of a digital acoustic signal.SOLUTION: An L-channel signal and an R-channel signal that are supplied from an acoustic signal input device 11, are added by an addition part 210 and supplied to a nonlinear processing part 211 as an in-phase signal. On the other hand, the L-channel signal is subtracted from the R-channel signal by a subtraction part 220 and supplied to a nonlinear processing part 221 as a reverse-phase signal. The nonlinear processing parts 211 and 221 are signal processing functions or compressors for applying nonlinear amplification according to a saturation function to input signals. An amplification factor of the nonlinear processing part 221 is smaller than an amplification factor of the nonlinear processing part 211. The reverse-phase signal is subtracted from the in-phase signal by a subtraction part 212 and supplied to a multiplication part 213. The multiplication part 213 outputs a subtraction result as an L-channel signal after reducing its amplitude by half. On the other hand, the in-phase signal and the reverse-phase signal are added by an addition part 222 and supplied to a multiplication part 223. The multiplication part 223 outputs an addition result as an R-channel signal after reducing its amplitude by half.SELECTED DRAWING: Figure 3 【課題】デジタル音響信号の再生音の表現力の幅を広げる。【解決手段】加算部２１０は、音響信号入力装置１１から供給されたＬチャネル信号とＲチャネル信号とを加算し、同相信号として非線形処理部２１１に供給する。一方、減算部２２０は、Ｒチャネル信号からＬチャネル信号を減算し、逆相信号として非線形処理部２２１に供給する。非線形処理部２１１および２２１は、入力信号に飽和関数に従った非線形増幅を施す信号処理機能、或いはコンプレッサである。非線形処理部２２１の増幅率は、非線形処理部２１１の増幅率よりも小さい。減算部２１２は、同相信号から逆相信号を減算し、乗算部２１３に供給する。乗算部２１３は、振幅を半分にしてＬチャネル信号として出力する。一方、加算部２２２は、同相信号と逆相信号を加算し、乗算部２２３に供給する。乗算部２２３は、振幅を半分にしてＲチャネル信号として出力する。【選択図】 図３