[PD] limiter~ problem

Tue Apr 20 15:01:08 CEST 2004

Hello list,

i'm now  testing zexy's [limiter~] and can't get clue of one thing.

according to the sound processing literature [1] the release time of a
compressor/limiter is the time of response to the signal's decrease
in level from one that is being compressed to one that is lower than
the threshold.
ok, that's fine.
but when i set the threshold level in zexy's limiter to, say, 95 dB,
and release time - to 300 ms and feed it an impulse,
rising from 90 dB to 110 dB and back, I find out that the release time
is in fact 750 ms !
May be this is some feature that i'm missing ?

To check it out i fed the same impulse to another
limiter, taken from the WONK's site[2], with the same
threshold/release parameters and got an opposite result:
the release time was just about 160 ms !

Where i can get a Mulder to find out the truth ?

What i need to know is the definition of release time in terms of zexy's limiter.
so i could predict the results of its output.
you will find the test-examples in the attachment.

thanks in advance !  

[1] = Introduction to Sound Recording by Geoff Martin:
http://nml.cult.bg/data/music%20research/audio%20engineering/Introduction%20to%20Sound%20Recording%20-%20Geoff%20Martin.zip
[2] = http://wonk.epy.co.at/work.pd/limiter/limiter.tar.gz

-- 
Best regs,
 Yury                          mailto:yurolog at mail.ru

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