[LAD] ANN: convoLV2 0.2

Bart Brouns bart at magnetophon.nl
Sat Oct 20 18:46:17 UTC 2012

You (Fons) obviously know your stuff when it comes to implementing
convolution, and I'm very grateful you gave us libzita-convolver, but I
have to disagree with this statement:

On Sat, 2012-10-20 at 12:00 +0000,  Fons Adriaensen wrote:
> Thirdly, for the use case of reverbs, the whole latency issue is
> just irrelevant. A reverb IR should not contain the direct sound
> (since this will be mixed in separately), and in fact the first
> 10 ms or so should be silence anyway, they don't contribute to
> the effect and just cause coloration. Which means you can adopt
> a scheme that permits arbitrary block sizes by allowing one (Jack)
> period of latency. Just remove as many samples from the start of
> the IR to compensate.

When you use a reverb plugin for ambience or things like the Bricasty M7
Bass XXL impulse, the coloration it is 90% of the effect you are using
the plugin for.
There is a whole range of useful coloration to be had by changing the
pre-delay within 0-20ms. Often it will sound best with 0ms, because that
how the maker of the impulse listened to it.
An ambience impulse is an important part of practically every mix I do.

That is why I am so happy with libzita-convolver and it's offspring :)
That is also why I would *love* latency compensation on buses in Ardour.

All the best,

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