[sdiy] Linear/Log FM (was "Living VCOs" PCB in 2009 ?)

[Simon Brouwer]

Mattias Rickardsson schreef:

> Having access to C on a detune knob seems very interesting indeed,
> especially when using more than one VCO simultaneously. Two VCOs could
> be tuned some Hz apart and the beating frequency would remain the same
> regardless of pitch.
> But how useful is it on a single VCO?

If all you have is a single VCO not much, you need at least a second one
to beat against.

I have been planning to include a single "linear detune" control on the
2-VCO synth I'm building. It should be an easy modification on the ASM-2
VCO: a pot connected between ground and -15V, two resistors to divide the
voltage down, a 10M resistor to inject current into the virtual ground of
the integrator, and a trimpot to null the offset voltage of the integrator
opamp.

-- 
Vriendelijke groet,

Simon Brouwer
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