What am I missing here: Limiting

[Chip Hitchens]

I really thought that I understood the basics of compression and limiting, but my results aren’t matching up with my expectations.

Using the onboard dynamics processor in my AW16G, I set up a limiter on one side of a stereo pair with a threshold of -2, different compression ratios between 1:10 and 1:infinity, very fast attack, decay around 350ms. There’s also a knee setting, which I assume should be hard for limiting. My goal was to keep anything really hot from going into digital distortion without affecting the natural dynamics of the recorded material.

For some reason, it made the effected channel slightly quieter across the board (when I bypassed the effect, both sides had similar levels). How is that happening? It shouldn’t do anything until the levels hit -2, right? I shouldn’t need to add output gain, since I’m not using it for traditional effect-type compression, should I? What am I doing wrong?

 

[Scottgman]

I'll give this a shot but my own newbie ineptness may shine through.

My understanding of compression-- when used to tame transients rather than as an "effect"-- is that the output gain is the whole point. You are compressing the peaks so you can make the average level of the track louder (by boosting the output gain) while not clipping.

So, in your case, if the track volume is too low, turn up the output gain on the compressor approximately the same number of decibels you are limiting. If the output meter on your compressor is showing a consistent -4db, then a good starting point is to boost the output gain by 4db.

If you don't have any problematic transients in the track and you aren't going for a compression "effect," then you should probably re-evaluate why you are using the compressor on that track.

 

[Chip Hitchens]

I record live classical music. It's extremely dynamic, and to get the quiet stuff audible, I have to run so that the loud stuff is within a few db of peak. That's fine for the music, but then the audience applauds and it's way over. Right now, I'm just sacrificing the applause to make the music sound the best I can--these are just archival recordings and are not for sale--but I would like to able to set a limiter so that I can keep all the dynamic range of the music and still have the applause in there without digital distortion.

If I have to use the output gain to do so, I'll probably just can the idea. I was only considering using the effects processor if I could be reasonable sure that the sound below the threshold of the compressor was going through unaltered. Maybe when I have a Crane Song or something...

 

[Scottgman]

Have you tried using two compressors? There is a post in this forum called Recording Screaming that discusses some issues similar to what you are dealing with. MassiveMaster describes a two compressor technique for recording very dynamic vocals. It might work in your situation also.

 

[mixsit]

I'd like to take a stab at this (although I've had only a brief session with the Yama
Are there any meters that would show how much limiting is actually going on?
If it is limiting, with the slow release, it could account for the volume loss. You'd expect the threshold number to be valid number though, but either way, you'll need to know what's actually going on.
Is it possible that it is not limiting, but the effect includes some general volume reduction? (Seems unlikely, but maybe try raising the threshold all the way up and see if it still pulls the volume down.
I agree with your saying a -2 setting shouldn't be hitting.
Something does seem out of whack.

"...I would like to able to set a limiter so that I can keep all the dynamic range of the music and still have the applause in there without digital distortion."

...IMHO you should consider volume rides or automation for this. It's a cleaner solution. Sounds like you want to pull the volume down in a controlled manner. Just a thought.
Wayne