Here’s an interesting board - a clone of the voices from the DR55 drum machine, without the sequencer. I bought two, I’m thinking I may build them into my SEQ on the DOUT chain. Four voices on each board - Snare, rimshot, hihat and bass drum, with accents.
Yeah, it should be possible to build it into a midibox pretty easily… There are a bunch of mods on it to adjust the tone/pitch/etc. of the voices, too. I’m thinking two boards with different settings might give a useful set of 8 voices.