- feed a 49,5 Hz (or 59,5 Hz) audio frequency into the Horizontal CV In or the Vertical CV In
I use this technique with a Vidiot. I assume it can work with other devices/modules. Maybe it’s a well known thing but I couldn’t see it mentioned anywhere.
You may have already tried routing audio signals into the horizontal or vertical oscillator CV inputs, which usually generates funny waves crazily spinning around. I found out (by chance) that some specific audio signals instead create very predictable and slow behaviours.
First, you need to be able to generate stable audio frequencies around 50 Hz (or multiples) and slightly modulate their pitch (say from 49 to 51 Hz). So get a VCO, or install a free app on your phone (that’s what I do), or properly program your synth (a Volca FM with Osc Mode = Fixed will do). I suggest to start with a basic sine wave. More complex waveforms will produce more chaotic movements.
EDIT: I use PAL, so this happens around 50 Hz. If you use NTSC, go for the range around 60 Hz.
Create a patch that uses the Vertical and Horizontal oscillators. Example:
Route your ~50 Hz audio frequency into a CV inputs. If you play exactly 50 Hz, the pattern will get deformed (proportionally to the loudness) but stay still.
As soon as you drift away from 50 Hz, the pattern will move (faster and faster).
Try also playing around multiples of 50 Hz (199-201 Hz, etc).
Example - Horizontal CV In:
Example - Vertical CV In:
I suspect interferences play a role, but I don’t really know what’s going here, which has been making it even more fun to play with. I look forward to your explanations.