I have a first working version of my polysynth. It has 6 independent voices, from left to right: MIDI controlled http://lookmumnocomputer.discourse.group/t/raspberry-pi-pico-dco, ADSR, VCA, mixer and PSU. ADSR and VCA are capable of eight voices but for now I only have the DCO with six voices at hand. It is still missing a VCF, LFO and so on but already has a quite nice sound. So next will be a board with VCFs and controls of the ADSRs need some more fiddling. I think it’s time to think about some casing.