@jasensmith said:
How would you use it in a Classical or orchestral setting? As an overall compressor, like for mastering, or on individual tracks, or both?
Hello Jasensmith
First of all for all of you who never used the parallel compression a short manual how to do it:
1. You need to copy the track which needs to be compressed so that you have it twice.
2. One track gets a compressor the other track gets nothing.
- The green curve below shows the track without a comressor (in is out)
- The red curves shows the channel with the compressor. A "very soft knee curve" is used here.
3. So use a ratio of 4 - 8 together with curves as we have them in the picture. Not all compressors are offering such curves.
The attack time can be longer than we normally use for rock and pop so 5-15ms instead of 0,1-1ms. Try different release times. Start with auto or ~200ms.
4. Sum both channels with a Bus - channel for example.
Important: You need to take care about the phase. You should have absolutely synchronous signals
What happens now?
Within the region A=light blue (low signals) we get an addition of the Signal of the green and the red track. The louder the signal the more we have no more addition (region B, light orange).
And finally with loud signals we only get a signal from the "green" channel.
This means that quiet signals will sound louder (we get it twice) and louder signals still have the original volume.
This way you don't cut or compress the signal but you make the quiet signals louder = less dynamic over all which can be usefull in classical music as you can read above.
For classical music it is enough to become quiet signals 3dB... 6db louder that's enough.
The opposite would be: Compressing the main signal (-3...-6dB). But this can kill transients or it can lead to pumping signals...
Another way could be to use both "systems": Just a little compression and just a little "up-leveling" with parallel compression.
In classical applications I always use the compressor very very carefully or I use one behind another.
I often use the parallel compresion in the output (mastering) channel.
Finally 3 things:
A) A lot of compressors have a dry/wet knob. Then you don't use a second copy of your audio signal.
B) If you want to use the parallel compression together with classical music you should look for compressors which can offer such "round"-knee-curves. I often use this guy here (pdf 10MB).
C) We normally don't have the problem of such loud and in the meantime also quiet signals when we are using samples because they all are well recorded for us. So the use of compressors in connection with samples may a bit differ.
All the best
Beat