| 摘要 |
PROBLEM TO BE SOLVED: To provide a balanced output type stereo amplifier which will not be damaged, even if it is connected to a three-terminal headphone. SOLUTION: The balanced output type stereo amplifier is provided with an operational amplifier 1 for applying non-reverse amplification to an input signal SL and output it, an operational amplifier 2 for applying reverse amplification to the signal SL and for outputting it, an operational amplifier 3 for applying non-reverse amplification to an input signal SR and output it, and an operational amplifier 4 for subjecting the signal SR to reverse amplification and output it, where the amplifier 2 is connected to a negative phase output terminal 10 via a resistor R1, having a resistance value which is identical to that of a voice coil resistance component R3 of the headphone, and the amplifier 4 is connected to the negative phase output terminal 12 via a resistor R2, having a resistance value identical to that of a voice coil resistance component R4 of the headphone. |
