[PD] up-down saw-wave

[Frank Barknecht]

Hallo,
Chris McCormick hat gesagt: // Chris McCormick wrote:

> > I wonder how hard it would be to implement the BLOP LADSPA algorithm  
> > in Pd, so that there would be native anti-aliased oscilators.  Its  
> > something that Pd sorely needs.
> 
> I am a big fan of these ones, by Günter:
> 
> <http://lists.puredata.info/pipermail/pd-list/2006-05/038681.html>
> 
> So juicy.

Another way to get alias-free waveforms is through summation formulas.
Attached is an implementation of the gbuzz opcode. Note that this
isn't actually bandlimited, but when choosing the harmonicity value
"a" not too high, high frequencies have reasonably low amplitue ...
and it's a patch I had here. The classical paper on this is James A.
Moorer's "The Synthesis of Complex Audio Spectra by Means of Discrete
Summation Formulas" available here:
http://www.jamminpower.com/main/articles.jsp

Ciao
-- 
 Frank Barknecht                 _ ______footils.org_ __goto10.org__
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