| 摘要 |
PURPOSE:To attain automatic sound volume adjustment of each channel by allowing a detection circuit to detect to which channel a sound signal comes from a sound source and allowing a control circuit to control the attenuation of the sound signal of a sound volume circuit of each channel. CONSTITUTION:A detection circuit 20 fetches a right channel sound signal 2, a center channel sound signal 3, a left channel sound signal 4 and a rear channel sound signal 5 and a level stored in a 1st storage circuit 24 is compared with levels of the right channel sound signal 2, the center channel sound signal 3, the left channel sound signal 4 and the rear channel sound signal 5 at a comparator circuit 25. A selection circuit 28 based on a signal A21 selects a 3rd storage circuit 27 into a 2nd storage circuit 26 as to a channel whose signal state is changed and a control signal 23 is used to change the attenuation of the sound signal in the sound volume circuit of the channel from a prescribed quantity to the maximum quantity. |
