[LAD] Harmonic generator and transfer function

Andrew Gaydenko a at gaydenko.com
Wed Dec 1 14:21:09 UTC 2010

On Wednesday, December 01, 2010 16:33:35 fons at kokkinizita.net wrote:
> > I'm afraid direct amplitude caculation in accorance with a0...aN will
> > produce "too fast" signal deviation, resulting in exceeding fs/2 band.
> Any non-linear transfer function will do this for some inputs.
> If you have an x^N term, anything above Fs/(2*N) will alias.
> If you want the nonlinearity without aliasing, you have to
> upsample (by a factor N, with N = highest power of x used),
> apply the nonlinear function, then downsample.

Fons, thanks! It is *that* trick I needed to eliminate my doubts wrt fs/2 
products :-) I think SRC is an approriate lib for up/down-sampling.


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