Hey hey,
I've been working with compress2 lately, but I have difficulties understanding 
the relationship between its parameters and typical compressors.

The attack, release and look-ahead times and the ratio are clear enough. But 
how about the low and high knee and threshhold?

The average compressor plugin has the knee hidden inside it and offers a 
threshhold, which is apparently not the same as compress2's threshhold, but 
rather more related to the knee values. I think.

Coming from Linux, I think of the Invada studio compressor, which offers
the following:
tight/sloppy: which is of no interest
Attack: kAtt in compress2
Release: kRel in compress2
Threshhold in dB: ?
Ratio: kRatio im compress2
Gain dB: a makeup gain, applied afterwards
Soft clip: of no interest here
Other compressor plugins offer similar controls, some adding a knee
radius or one value knee setting, others can set a look-ahead time.

Can someone give me a little guidance? An article that explains the 
relationships between these settings would be good enough.

Best wishes and thanks,

Jeanette

-- 
  * Website: http://juliencoder.de - for summer is a state of sound
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Hi Iain,
many thanks! This makes sense and would be very easy to work with.

Best wishes,

Jeanette

Dec 18 2024, Iain McCurdy has written:

> Hi Jeanette,
>
> Your assumptions about threshold, low-knee and high-knee are correct.
>
> Threshold in compress2 is not how it would be understood in a generic compressor; it is the threshold of a separate noise gate. The threshold, as it would be understood in a generic compressor, is the mid point between low-knee and high-knee. Therefore, if low-knee is -40 dB and high-knee is -30 dB, the compressor threshold is -35 dB. Some implementations offer a control over knee size, which in this example would be 10 dB.
>
> I hope this is correct!
> Iain
>
> ________________________________
> From: A discussion list for users of Csound  on behalf of Jeanette C. 
> Sent: 18 December 2024 14:39
> To: CSOUND@LISTSERV.HEANET.IE 
> Subject: [Csnd] compress2: general relations between parameters and usual compressor settings
>
> Hey hey,
> I've been working with compress2 lately, but I have difficulties understanding
> the relationship between its parameters and typical compressors.
>
> The attack, release and look-ahead times and the ratio are clear enough. But
> how about the low and high knee and threshhold?
>
> The average compressor plugin has the knee hidden inside it and offers a
> threshhold, which is apparently not the same as compress2's threshhold, but
> rather more related to the knee values. I think.
>
> Coming from Linux, I think of the Invada studio compressor, which offers
> the following:
> tight/sloppy: which is of no interest
> Attack: kAtt in compress2
> Release: kRel in compress2
> Threshhold in dB: ?
> Ratio: kRatio im compress2
> Gain dB: a makeup gain, applied afterwards
> Soft clip: of no interest here
> Other compressor plugins offer similar controls, some adding a knee
> radius or one value knee setting, others can set a look-ahead time.
>
> Can someone give me a little guidance? An article that explains the
> relationships between these settings would be good enough.
>
> Best wishes and thanks,
>
> Jeanette
>
> --
>  * Website: http://juliencoder.de - for summer is a state of sound
>  * Youtube: https://www.youtube.com/channel/UCMS4rfGrTwz8W7jhC1Jnv7g
>  * Audiobombs: https://www.audiobombs.com/users/jeanette_c
>  * GitHub: https://github.com/jeanette-c
>
> Cinderella's got to go <3
> (Britney Spears)
>
> Csound mailing list
> Csound@listserv.heanet.ie
> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
> Send bugs reports to
>        https://github.com/csound/csound/issues
> Discussions of bugs and features can be posted here
>
> Csound mailing list
> Csound@listserv.heanet.ie
> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
> Send bugs reports to
>        https://github.com/csound/csound/issues
> Discussions of bugs and features can be posted here
>

-- 
  * Website: http://juliencoder.de - for summer is a state of sound
  * Youtube: https://www.youtube.com/channel/UCMS4rfGrTwz8W7jhC1Jnv7g
  * Audiobombs: https://www.audiobombs.com/users/jeanette_c
  * GitHub: https://github.com/jeanette-c

Loneliness up ahead, emptiness behind <3
(Britney Spears)

Csound mailing list
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https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
Send bugs reports to
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Discussions of bugs and features can be posted here