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Subject: Re: [korgpolyex] Re: FM-800 mod

From: Atom Smasher <atom@...>
Date: 2006-04-11

On Tue, 11 Apr 2006, austeritygirlone wrote:

> Since there is voltage control available for pitch it is probably even
> possible to do some kind of real FM. But since there's only one osc, it
> will be self-modulation. And the osc isn't designed for this either so
> it will probably result in some kind of wierd sounds. Especially, since
> we don't have smooth waveforms like sine waves.

it seems that the DCOs exist virtually in IC3. if that's the case, they
wouldn't respond well to any modulation in the audio range.

my ∗guess∗ is that it would be unusable noise.

> If you take a closer look at the schematics, the pitch-bend output of
> the IC8 multiplexer feeds into the oscillator clock control circuit.
> This is also where vibrato gets inserted into synthesis.

DCO implemented in old hardware: pitch bend and vibrato are slow enough
for the DCOs to track... i have my doubts about FM in the audio range.

> Maybe it's possible to route bend to filter cutoff via a switch,
> allowing joystick control of the filter.

or just use the moog slayer mod... you can use a joystick instead of 2
knobs, if you prefer ;)

seriously, you can find 2 axis joysticks in electronic surplus catalogs,
although you'll probably want to change the pots from linear to log taper.


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