[sdiy] C0G/NP0 caps for VCOs

[David G Dixon]

> > I don't know what you folks have been using for VCOs lately 
> but these 
> > look like a pretty good substitute for polystyrene capacitors :
> >
> >   Samsung CL31C124JOHNNNE
> >   120 nF 16 V
> 
> Maybe a bit large for an audio-rate VCO perhaps?  Typical 
> values for audio range would be hundreds of pF, maybe 1n0.
> 
> Good for a VCLFO though - the DuaLFO uses 100nF to cover the 
> range ~90uHz to 45Hz.

I've tried to use larger NP0 caps to switch into for getting LFO range in
self-oscillating filters.  However, I've always found the leakage to be too
high (couldn't get stable oscillation at very low frequencies), and have
then replaced them with polypropylene (WIMA -- the little red bricks), which
work extremely well (no problem oscillating stably at low frequencies).