| 摘要 |
PROBLEM TO BE SOLVED: To enable acoustic signal processing suited to an input signal by detecting the presence/absence of the input of a multi-channel acoustic signal input part and switching an acoustic signal switching part by a detecting result. SOLUTION: A multi-charmel acoustic signal from an input terminal IC is inputted to a detection part 9, which detects the presence/absence of the input of a multi-channel acoustic signal to send a detection signal to a control part 15 at the time of the presence of input. When the detection signal of the part 9 occurs, the part 15 switches the input of a switch 4 to an E side to switch to the input of a multi-channel acoustic signal. When the input of the multi-channel acoustic signal can be discriminated to be absence, an error flag is outputted from a demodulator 7 to send this error flag to the part 15. When the error flag is inputted from the demodulator 7, the part 15 switches the input of the switch 4 to a side D to switch to the input of a two-channel acoustic signal. Thereby, acoustic signal processing suited to the input signal is enabled. |
