Konversion: Eurorack to Kosmo

See Power supplies choices? for discussions of power supplies for Kosmo. It’s the same as Eurorack, except that the little-used 5V bus and CV and Gate lines in Eurorack are not used at all in Kosmo.

For the SSO, it depends on the transistor. Most transistors need more than 12V to oscillate. It’s possible to use a ±12V supply for one of those by connecting it between the +12V and -12V buses, that means it has a 24V voltage difference — and then the output would need to connect between the transistor and the ground bus. But an easier approach is just to use a transistor that will work on a lower voltage. I bought a bunch of SS9018 which were reported to go into avalanche at a little above 8V. Using one of them you can make an SSO that works on a single 9V battery, or just the +12V from a synth power supply.

Sam’s promising to release his MegaDrone board and schematic soon, that’s based on 10 SSOs with voltage control. I don’t know but I think it uses SS9018. Even if you don’t want the whole huge board, the schematic might supply some good ideas.

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