Interesting Paper available on Moog VCF

[Thierry Rochebois]

>What do you mean by "implementation"?

It can be easily implemented on the DSP 56001 as a "normal" digital filter
with less than 10 instructions.

>Not being able to hear aliasing (which has more to do with waveform
>generation anyway) in a music store environment is a far cry from
>having the full-tilt "gazorch" and "balls" of the Moog VCF.

True. But, you will hear this aliasing effect on any other digital
synth even in this environment.
You can also hear the signal/noise ratio of low quality analogue stuff
(not the Moog of course).


>Analog nonlinearities are extremely difficult to implement digitally.
>When you add a digital nonlinearity you create an infinite number of
>harmonics, and these alias around and sound pretty crappy.

It depends on the way you perform it... If you mean look up tables ;-)

>>My example is Ralph Deutch, he worked for
>>   Kawai and patented more than 136 devices... And nobody knows him.

>A patent *is* published, that's the point of it!

That's true. But the CCRMA people and other university people don't
seem to read patents (just look at their bibliography).

By the way, it would be nice to do a patent web page, with comments and
all that... if anyone is interested...

Thierry Rochebois

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