[LAU] [LAD] [ANN] CAPS 0.9.12

Tim Goetze tim at quitte.de
Sat Aug 24 22:21:52 UTC 2013

[Fons Adriaensen]

>I've learned to mute monitoring while doing such tests...

I was suspecting you had :)

>> It adds to the evidence that implementing thorough control
>> smoothening is inevitable in the long run.
>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.

I'm planning to evade this problem by crossfading between two parallel
static filters.  Some phase mismatch issues can probably be expected
when the parameter sweep covers a larger range, but I'm hopeful it
will turn out not to be much of a problem in actual practice, and that
we will find out soon.  It really needs a fix.


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