[sdiy] VCLFO and VCADSR details available online

[Aaron Lanterman]

On Tue, 19 Dec 2006, Tom Wiltshire wrote:

> modulations in the digital domain is certainly one way around this 
> problem, but again, the easiest way to do this is to have one big 
> powerful processor that deals with it all. I've wondered if one 
> 'modulation processor' per voice might be a half-way house. It'd need to 
> be fairly fast, but might not need to be hugely powerful. This would 
> generate 2 or 3 envelopes and an LFO or 2 for each voice. All modulation 
> routing would be done digitally and the chip would just output a few 
> summed voltages to go directly to filter cutoff or wherever.

The oddly named Oberheim OB-Mx is set up like that. Each voice card has 
its own microcontroller, and then there's the master board that has a 
microcontroller that talks to all the voice microcontrollers:

http://users.ece.gatech.edu/~lanterma/obmx

Took me a long time to find someone in the department with the right old 
equipment to read the ROMs...

- Aaron

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Dr. Aaron Lanterman, Asst. Prof.
and Demetrius T. Paris Junior Prof.  Voice:  404-385-2548
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