Hi, Julius. I understand.

See this:
https://github.com/grame-cncm/faustlibraries/pull/37/commits/8f1bd1ba78ff4919637a9bfd9ec635225cfb4ba5
.

That's a basic lookahead limiter based on this post:
http://iem.at/~zmoelnig/publications/limiter/.

This algorithm is even simpler: it just calculates the amplitude profile
using a peak-holder and it smooths out attack and release using,
respectively, a one-pole lowpass and a peak envelope. Those filters are
based on the e^(-2pi) time constant (Chamberlin's design for 1pole
filters). This time constant works in this case as the input delay is set
by the attack of the system, so the amplitude profile to calculate the
scaling factor roughly reaches its maximum after the attack time. The
release time might be changed with some other constant, if more appropriate.

Personally, I'm satisfied with it but I also designed it for my specific
case, that is, stability in self-oscillating systems. I needed a cheap
solution with low distortion; I'm not sure if this works well for most
applications. People are invited to test and comment.

I had a look at Zölzer's limiter, pp 231 and 232, but I don't quite
understand what "the slope of the limiter" is. What do you think? He also
doesn't mention a specific delay for the input path but I'd assume that it
is the same as the attack time.

Dario


On Sat, 23 May 2020 at 01:38, Julius Smith <[email protected]> wrote:

> Hi Dario,
>
> Yes the current limiter is simply a compressor, using the usual (causal)
> amplitude follower, that applies a ratio of 4 starting halfway up (-6 dB).
> Please feel free to make us a new one that is nicer!
>
> Julius
>
> On Fri, May 22, 2020 at 11:19 AM Dario Sanfilippo <
> [email protected]> wrote:
>
>> Hello, list.
>>
>> Am I missing something with co.limiter_1176_R4_mono? I see that there is
>> no lookahead mechanism inside and, if I test it with a song at +60dB, the
>> output of the limiter is rather consistently at about 25 dB.
>>
>> Best,
>> Dario
>> _______________________________________________
>> Faudiostream-users mailing list
>> [email protected]
>> https://lists.sourceforge.net/lists/listinfo/faudiostream-users
>>
> --
> "Anybody who knows all about nothing knows everything" -- Leonard Susskind
>
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