Circuit Bent/Augmented Yamaha Pss-80

video by SMMP

"I always loved the Yamaha PSS-80 keyboard, for its lo-fi, almost 8bit, squarewavey sounds. Given it's polyphony, I thought it would be a lovely keyboard if it had a nice filter. So I "augmented" it (rather than bending it) sticking in a filter (I think based on the old Wasp Synth VCF), add a delay, put an LFO that can modulate either the delay or the filter, and a monster on the left side, some kind of pitch tracking, which I built following some instructions in the CD4046 datasheet, but then creating loops with the signal and lowering it down with a CD4040 frequency divider chip. The switches there and the pots, don't always provide nice results, but when they do, they can shake your pants!

Enjoy!"