This one is a re-build of one of my first ‘designs’, if you can call them that way. Nevertheless, It’s a percussive module designed for all kinds of metallic sounds; cymbals, hihats, gong, bells, plate hits, cowbells, trash cans, … you name it. Since I’ve build the first one I’ve been using it in every song since. It’s actually a very useful and versatile percussion module. At that time however I didn’t really had the habit of writing down schematics, I just soldered things together until it worked. Yet I wanted to revisit this module again because I could use a second one and I also wanted to iron out some of the quirks my initial build had as well as add a few features I regret not having on the first module. So I kinda started over, this time taking notes though.
While doing research for the oscillator I stumbled – seems to be a common theme — upon these IC’s. The ICL8038 promises to be a stable oscillator with very few external components. It’s an obsolete product, but I could get a few of them via Ali-express cheap enough to experiment with. Since it offers a sine output I immediately thought about doing some FM type percussion. That way I wouldn’t need 1/v per octave and pitch fluctuations wouldn’t be that much of a problem either. I also had a V2164 quad VCA chip around, so a 4 operators (aka oscillators) seemed a perfect fit. Enough to provide some interesting FM timbres at least.
I always wanted to build a ‘clap’ sound module that’s not a one on one re-creation of the 808 or 909 and has a bit more control. I liked the sound on the Vermona DRM, so something like that, but not quite the same.