[PD] distorsion

Tue Nov 15 18:38:14 CET 2005

Hallo,
Thomas Ouellet Fredericks hat gesagt: // Thomas Ouellet Fredericks wrote:

> "remapping the signalvalues according to a stored table" Remapping?
> Like ring modulation but with a different wave than a sine?

No, it's not ring modulation. With wave shaping, you use the incoming
signal to look up values in a (function) table. See attached patch for
a basic example. If the shaper table would contain a plot of the
function "f(x) = x", then the incoming signal would pass unchanged.
However any deviation from f(x) = x will change the signal and distort
it. Because just a table lookup is involved, this technique is very
cheap on CPU and thus is very popular, wherever CPU power is limited
(as was the case through the whole 1970s). 

Also see the Chebyshev-example in the Pd docs:
3.audio.examples/E05.chebychev.pd

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