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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.


--
...atom

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