Quick guide: First: I must tell you that. how is this headphone amplifier design. Actually it’s tube buffer + amplifier work model.both function is alone, the music input to 6J1 tube buffer preamp and output to daul NE5532(TI)(each chip for each channel) amplifier part, after music output to your headphone. else ,In back of the P2-1. you will find a OUT interface. that the 6J1 buffer preamp pure output.you can use it as a buffer preamp for your other power amplifier, that’s interface music isn’t through the headphone amplifier part.so. it’s very helpful for install it in your home audio system too. get more warm sound. Secondly: this P2-1 powered by 12VAC, and this list included a transformer already. with both voltage for choice. 110V
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