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Re: [korgpolyex] Re: FM-800 mod

2006-04-11 by Atom Smasher

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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