On Sat, Aug 24, 2013 at 09:56:47PM +0200, Tim Goetze wrote:
> Thanks a lot for the evaluation and the problem report; I hope this
I've learned to mute monitoring while doing such tests...
> It adds to the evidence that implementing thorough control
That may or not solve the problem. You have 3 input parameters
(P), and 5 biquad coefficients (C). Interpolating the C can
make a biquad unstable, and if this happens it doesn't matter
how fast or slow you do it. The only solution is to interpolate
the C only between sets of values that correspond to values of
the P that are not too far apart. So you need two levels, first
on the P to limit the rate of change of the parameters, then on
the C to avoid zipper noise.
> >Apart from this, it also produces multiplicative LF noise
The noise remains below audible levels in this case (there
are some plugins that are much worse). But it is still much
higher than it should be. The reason is that a biquad is not
the right filter for this job, at least not at low frequencies.
A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)
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