Diplomat – DIY PCB


This is a PCB set for building your own Diplomat preamp. This is not a beginner project, so if you’ve never built a pedal before, then this isn’t for you.

I’ve tried to make this as affordable and as easy to assemble as possible, but this is a high-voltage circuit and requires special care in assembly, testing, and use. Sushi Box FX is not responsible for any damage or injury caused by improper handling, assembly, or use of this circuit.

Diplomat is based on the EF86 channel of the Matchless DC30, which is a single-stage pentode preamp. By itself it will only ever run clean, but you can use it as a clean boost to push a pedal/preamp/amp, or you can push it into overdrive with another pedal.

Each PCB also includes a “SUSHI SWITCH L” 3PDT footswitch PCB and a “EF86-EZ90” PCB for mounting the tube socket. A pre-drilled enclosure is available for an additional cost.

You can find the build document with the BOM, schematics, and enclosure drill guide here.


40 in stock

  • Options Price: $0.00
  • Product Price: $18.00
  • Total: $0.00