We’ve done lots of work to these and other drum machines. Mods have included the following
- Individual output for drum sounds
- Footswitch for metronome
- Expression pedal for balance
- MIDI Clock input
- External Speaker Jack
- Line Input
Here the inside with a new PCB added above the clock divider board to support the functions above.
This is how we implemented the MIDI clock input
And here is a schematic and layout of the sound PCB. This was a couple of days work!