[LAU] upwards compression

[Jörn Nettingsmeier]

On 12/25/2010 03:57 PM, Fabio wrote:
> Em Sat, 25 Dec 2010 14:41:19 +0000
> Q <lists at quirq.ukfsn.org> escreveu:
>> Well it's easy enough to set up in Ardour using a bus and a regular 
>> compressor. I expect it should be easy enough in other software.
>>
>> Q
> 
> how you do that? none of the compressors i checked has ability to use
> negative ratio.
> upwards compression means it elevates volumes below threshold instead
> of the "opposite"(lack of word) in normal compression

you can set up two busses, both fed from the signal you want to
up-compress. one is left as-is, and the other is set for compression at
the threshold below which you want the up-compression to set in.

now you mix both buses to the same master. the effect is that at low
levels, both signal paths will be uncompressed and add up. at higher
levels, the compressed signal path is attenuated and adds less gain,
which is the effect you're after.

there's a million variations of this scheme, you can do the same with
expanders.

at some point, sampo savolainen was working on a really nice compressor
that includes a parallel signal path - i don't know if it was ever
released, but it might be somewhere in his svn...