VCF-1 – Vactrols

I’ve been asked if I could do a workshop about synth building. While there are no solid plans to do so yet, I was thinking about what to build during such a workshop. It would be cool to have something to take home you’ve build yourself during the workshop, and even better if it was actually useful. While I was thinking more along the way of simple CMOS based noise-making machines, I was asked whether a filter would be possible. People like filters and if it could be CV controlled, it could be useful even for more advanced synth enthousiasts.

(edit: a workshop has been planned @ the pulse modular music festival in Opwijk, Belgium on 15/06/19)

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I found myself short of an ADSR in my system and it annoyed me to no end I hadn’t thought of buying a few more. Instead of hitting the favourite Eurorack module dealer for my fix I went googling to see if I could cook up one of my own. Couldn’t be that difficult. Right. Turns out, there are tons of useful ADSR schematics floating around on the internet. Continue reading “ADSR”

The Oscillator One

Since Coolaudio started reissuing old IC’s used in various synths I always eyed the V3340, which is a reissue of the CEM3340 chip as used in many classic synths such as the Roland SH101, Prophet 5, Memory Moog and plenty of others. It’s, in essence, a fully featured 1V/oct oscillator on a single IC and thus takes away a lot of the headaches inherent to VCO design. Things like linearity and temperature compensating are taken care of for you. This takes away a lot of the pain of building VCO’s, in fact, since these IC’s are available again a DIY polysynth starts to become a possibility.

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