Details:

The circuit is based on the very expensive kondo (audionote) M77 model

Tube preamplifier, compatible with Phono amplifier. The Phono amplifier part can be closed under independent control

Tube model: 6X4 (ez90) * 1, 12AY7 (6072) * 8

TRW and GOOD-ALL bakelite sealed coupling capacitors and gold-plated electronic tube sockets are used for signal channels

It is designed to turn off the Phono amplifier function independently, switch the signal of 4-channel relay, and reserve a way to add chokes by yourself

PCB size: 220 * 290MM

Transformer voltage:
AC250V~0~ AC250V@100mA
0~ AC12.6V@3A
0~ 6.3V@2A

Gold-plated PCB on both sides

4 ways audio input +1 way audio output

Package included：

M77 preamplifier board PCB x 1

Note：This is diy pcb ，not included any parts ！

Suitable chassis：https://www.ebay.com/itm/354553427246

Assembled board ，just for reference：

https://www.ebay.com/itm/354553414394