MOTM

((solder break...received '600 uSeq proto boards today!))

I think this is going about it the wrong way.

More complicated, but more controllable is to get a mechanism to "push & pull" the bow across a
string. Not a regular bow, a small one (say 4 inches). I would do this:

a) get surplus stepper motor for $7
b) get sample of stepper motor driver IC (www.microlinear.com), TI has them, etc.
c) use $5 PIC to drive IC
d) use on-chip ADC of the PIC to have 2 inputs: speed and depth (like an LFO)

This is a simple setup: 2 ICs and a <100 line program

Paul S.