VCOs as modulation sources

[Christopher List]

Hi DIYers - 

This is more a "Modular Heaven" topic than strictly DIY, but I thought this 
would be the best forum for it. 

Last night I got the EN "Timbre Modulator #2" mounted to the panel and 
installed in my modular. This does 0 rectification through full wave 
rectification of the input signal (with a pot control). Then it does VC xfading 
of this signal with a squared-up version of the original signal. It's also the 
second timbre modulator in the Barry Klien book. 

Anyway, I set it up with a sawtooth wave in. I set the CV input to another VCO 
- in tune with the first one. This created some great waveforms depending on 
what wave shape the CVing VCO was set to and what I had the FWR amount set to. 
Really interesting sounds that went from "quantized" type sequencer-generated 
waveforms, to (as you might expect) FM type waves, to weird resonant waveforms. 
Kinda different from any sound I had ever gotten from the modular while still 
being very musically useful. 

It occurred to me that the VCO as modulator, in tune with the audio VCO, and 
controlled by the same CV is one of my favorite modular routings. Using it for 
things like audio frequency xfading, amplitude modulation, PWM, and of course 
FM (of VCO's and filters), always seems to create really cool thick sounds. One 
of the nice things is that you can "pinch" the pitch of the modulating VCO with 
little cv's and get the sound to jump into weird side-band frequencies before 
settling back in tune - or run the pitch CV of one VCO through portamento, and 
the other one straight for a similar effect.

I was wondering if anyone had any other interesting uses for this type of 
modulation they might like to throw out for discussion...

- Chris