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Old 12th May 2015 | Show parent
  #72
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Quote:
Originally Posted by Klonfocius ➡️
Paul said 008 was 8 Monowaves in box but i believe it's more like his defender voice board, the PCB shure look like that. Monowave uses a phase accumulator who clocks a external counter that counts adresses from a ROM and phase acc's is no real variable sample rate rather "skip bit" principle albeit the counter acts as a "limited jitter filter".008/Defender voice board uses 3 AT Megas each seams to use the phase accumulators to count internal FLASH for waves if so 008 is quite like non BLIT DW8000 or a ESQ1 unless he uses other principles to count and there are several to chose from. Paul used to talk alot about PPG old phase accumulator design which uses trixes to get around the traditional phase accumulator design limitations.Paul was asked similarely questionas from someone else in the Modulus 008 thread but newer replied , perhaps he didnt know how to answer?!
My assumption from what Maddox wrote, and looking at the schematics of the Monowave (Though there is a bit I just can't work out), I think there may be something missing off the schematic I'm looking at, the AT Mega is used to generate a sample clock (with a bit of jitter if they're not using a simple counter since the master clock is a fixed oscilltator), which is the used for an external sample position counter which is always incremented by one each time. So what we get is in effect a variable sample rate, albeit with some jitter.

The ESQ1 on the other hand would skip samples at higher playback pitches, which is rather different. I supposed at lower pitches you could say it is similar to the way the Monowave works, but with way higher jitter of the point when the output sample is changed.

Another way of looking at it would be to say that they are both effectively the same as resampling the output of an ideal variable sample rate oscillator, but the Monowave resamples at a considerably higher sample rate, with reduced aliasing as a result.

I'd like to see a schematic of the defender, I can't find any info on it so far.

Last edited by Jon Hodgson; 12th May 2015 at 01:12 AM..