[sdiy] Prophet VS a phase accumulator design?

[Tom Wiltshire]

There's a bit about it in "The birth of the prophet VS":

http://www.vintagesynth.com/sci/birth.txt

Quote:
Tony and I theorized on how to do a wavetable synth, and came up with two strategies - have a 
waveform of short, fixed length and vary how fast you played it, or start with a very long 
version of a waveform and skip samples in it to alter how long it took you to read it out once 
(and therfore alter your final pitch). Unable to decide we acquired a PPG anda Korg DW6000 to 
see how they did it. We felt vindicated to learn that the PPG did it exactly the first way we 
theorized, and the Korg the second. (In the process, Josh became one of the few people in the 
US who knew how a PPG worked inside - the company didn't release schematics, advising would-be 
techs to "Don't loose (sic) time - return to factory immediately!"). We liked the pure balls 
of the PPG better (plus the scheme that used shorter waveforms meant we could stuff more waves 
into the instrument), so we chose the transposition method.

HTH,
Tom


On 1 Feb 2011, at 21:11, karl dalen wrote:

> Where the Prophet VS a phase accumulator design?
> It sure do look quite similar to the DOC chip in
> ESQ1, yet 12 bit instead of 8. 
> 
> Reg
> KD
> 
> 
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