[PD] attack/release for spectral gate [was: is this a spectral gate?]

[Kevin McCoy]

Hello all,

A while ago I was working on a spectral gate patch and now I've come
back to it.  Here's a quote from Tom Erbe's earlier email:

"For a spectral gate, just calculate the amplitude from real and imag,
make your gate decision based on the amplitude and threshold, and
then apply the same gain reduction to both real and imag. Add attack
and release to the gate-gain for smoother results."

I want to add the attack and release so it sounds smoother and less
bubbly/harsh (know what I mean?)  I am racking my brain trying to
figure out how to do this to each of the frequencies.  The soundhack
vst does this really nicely and even has a visual representation of
the gate where you can see it rise and fall with attack/release for
the whole spectrum.

The problem for me is persistence across different blocks.  I suspect
[line~] doesn't work for this as it does for amplitude attack/release
implementations.  For example, if there is a spike around 3000 Hz, how
can I carry that attack and release across several blocks of audio?  I
used delay objects with what I thought was some success, but I don't
think I had it right.  I have attached the patch which is basically
what Frank posted earlier - it does not have any of this yet and is
just a hard on/off.

Much confusion, I would be grateful for any help!
Kevin
-- 


++++
http://pocketkm.blogspot.com
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