The Yamaha CS series has some unique features inside and out. Most of the circuitry uses quite unusual IC’s (custom perhaps?) . The VCO for a start uses an interesting method of resetting the core, I can’t really go into detail because I can’t exactly understand what is going on but it creates a very stable oscillator that was used in the polyphonic part of the CS series. It has quite a pleasant band-pass filter and very fast attack settings, it can sound a bit sterile but its unique-ness pays off for that.
Here I added a sub-octave taken from Yves Usson’s schematics, except I added a couple more flip-flop’s to create 2 more octaves below! I thought this would be interesting because the VCO has quite a range, so you can end up with 2 pitches 4 octaves apart!
Sound Samples soon!