[sdiy] more questions about Walsh functions and generators

[Neil Johnson]

> Now what would be interesting would be to have some intelligence
> to the drawbars to synthesize some intuitive wave shaping...

Of course, you could do a Fourier->Walsh transform on the drawbar values,
so it "behaves" like sinewave additive (Hammond) but is actually done in
the Walsh domain.

Personally, thats like "virtual analogue" -- gee, its a box with knobs
marked "OSC" and "FILTER" so it MUST be analogue, right?  *thwack*

As for how many, Risch and Brubaker came to the conclusion that 32 is
about the minimum number of Walsh terms you need to comfortably
resynthesize any waveform, being comparable to a low-pass filtered DAC,
and better than that for 64 terms.  I'd say the optimal is 32 terms.

Controlling 32 Walsh coefficients will be fun anyway!

Neil

--
Neil Johnson :: Computer Laboratory :: University of Cambridge ::
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