| 摘要 |
PURPOSE:To prevent a sound image from being blurred at the time of monoral signal reproduction. CONSTITUTION:Left and right input voice signals are added by an adder circuit 32 and supplied to two input terminals of a switch circuit 33. The first output terminal of the switch circuit is connected to the input terminal of a first amplifier circuit 36, and the second output terminal is connected to a second amplifier circuit 37. The positive terminal of a left side speaker 27 for enlarging a sound field is connected to the output terminal of a left side amplifier circuit 23 to be connected to a left side speaker 25, and the negative terminal is connected to the output terminal of a first amplifier circuit 36 to be connected to the positive terminal of a superwoofer speaker 29. The positive terminal of a right side speaker 28 for enlarging the sound field is connected to the output terminal of a right side amplifier circuit 24 to be connected to a right side speaker 26, and the negative terminal is connected to the output terminal of a second amplifier circuit 37 to be connected to the negative terminal of the superwoofer speaker 29. When a stereo signal is inputted, a switch circuit 33 is turned off and when a monoral signal is inputted, this switch circuit is turned on. |
