Here is a patch created entirely out of VCO Unit modules except for some Delay and Reverb effects at the end. Patch explanation is below the video.
VCO Unit abuse.vcv (4.5 KB)
1 - Clock / Sequencer
This one is fairly straight forward. There are 3 VCO Units in LFO mode using square waves. The lowest frequency syncs the other two to keep them in phase. The middle frequency is one octave up, and the high frequency is two octaves up. The two lower frequency outputs are attenuated by the Level and summed to give a pleasing 4 step V/Oct sequence, and the highest frequency output clocks the envelope generator and syncs the rest of the patch.
2 - VCO (audio rate)
This is as obvious as it gets. Some shape and linear FM modulation is thrown in to get an interesting sound.
3 - LFOs
Again, these are obvious. The first LFO modulates the Level of the second, and the second modulates the envelope generator.
4 - Envelope Generator
Now it gets interesting. The VCO Unit is in LFO retrigger single shot mode using the triangle wave form and skew shape mode. The shape can vary from descending ramp to triangle to ascending ramp. The shape CV modulation adds interesting spikes to the envelope. Because the modulation itself is modulated, the intensity of the spikes varies. The envelope is triggered by the “clock” LFO at the hard sync input.
5 - VCA
This is the least obvious use. The VCO Unit is in 0 Hz carrier mode without any FM or phase modulation. The triggers at the sync input guarantee that the 0 Hz signal is always at phase 0, meaning the oscillator output would be constant 0V. The envelope at the Level input attenuates the signal appearing at the Offset input. It ends up functioning as a very standard VCA.
Some additional uses
Starting with the VCA arrangement, take away the Level CV and put the Level knob to 100% and the Offset CV amount knob acts as a simple attenuverter for the Offset CV input.
Also take away the Offset CV and the Offset knob becomes a constant voltage source.