YouTube via boobtube356 "Doepfer A-196 PLL tracks Plan B M15 VCO. PLL output passes through Plan B M12 bandpass filter and then is ring modulated with the M15 sine output. The result goes to the Makenoise QMMG. The background is a Cwejman VCO-6 sine going to Doepfer A-137 wave multiplier, then ring modulated with Cwejman MMF-1. The result goes to the Cwejman VCA-4MX and is then panned at audio rate by a Cwejman VCO-2RM. Sequence is from Doepfer A-160/1, A-152, A-143-3 and Plan B M14."
YouTube via EA78751 "four new analog drum circuits inspired by the TR808, sequenced by algorithms. dronematrix is being gated thru the toms.
birdbox (white box) is the sequencer JBoT (black box) is the toms & dronematrix cowbell is the middle board the front board is a bastard circuit based on the 909 rimshot.
via GB "I designed the electronics and firmware for the chording keyboard in this alternative MIDI controller in the early 90's. It was made using a set of Yamaha DX7 key contacts. These contacts have both make and break contacts which allow for velocity sensing. The firmware was done in 8031 assembler and the source code is posted on my website, www.MusicTechnologiesGroup.com. The project was presented at various conferences and symposiums around the world."
Note the ribbon controller and additional buttons on the joystick.