| 摘要 |
PURPOSE:To reproduce stereo sensation of small antiphase feeling by providing two high pass filters HPF, three low pass filters LPF, a audio removing means and two adders, dividing input signals to two frequency bands, and inputting only output signals of the LPF to the audio removing means. CONSTITUTION:The whole audio frequency band F0 is divided into frequency band F1 of 10Hz-5kHz and frequency band F2 of 5-20kHz making about 5kHz a boundary. Antiphase feeling of reproduced sound is lowered by inputting only frequency band F1 as input signals S1 and S2. To reduce antiphase feeling, it is enough to make upper limit of frequency band F1 small. As aural signals do not contain frequency band lower than about 100Hz, input signals S1 and S2 are added by an adder 22. The third LPF 19 having input/output frequency characteristic of a curve Y3 passes only the frequency band F3, and augments lowered sound volume. |
