Mid Side Compression offers powerful way to enhance the space and air of your mix when it's mastered.
If it needs it of course!
Many times I talk about mid side mastering as a remixing tool. And this form of compression offers a dynamic alternative when static methods such as mid side EQ fall flat.
If compression needs to be used at all on a mix, conventional methods take priority. Any mid side variation of any process is by nature used infrequently. It’s a special bag of tricks only used for special occasions.
So before reading about the more esoteric forms of compression, you might want to review what the basics of mastering compression can do. Otherwise I’ll answer your next pressing question:
It can anchor a mix.
It can add a special punch if ordinary methods fail.
It can warm up vocals; or tame “pushy” vocals.
And, like any process, it can wreak havoc on a mix, in lesser hands. One of the more detrimental mistakes of mid side compression is to cause a noticeable widening and narrowing of the stereo image, working against the intentions of a mix.
However set just right, vocals, for instance, can sit better in the mix. And as an added benefit, beautifully enhance the stereo space in a subtle way.
Although I’m focusing on vocals, I have to be careful to point out that everything in the Mid channel will be affected. And this also assumes the vocals are panned in the center in the first place!
The special punch factor comes into play when I adjust the makeup gains for the Mid channel. Note, though, a side effect (no pun intended!) of this process, is that the stereo image could narrow noticeably. But this can be a benefit for a mix like this...
...by using multiband compression in mid side mode. I can address issues more precisely.
For example, if sibilant vocals are just in the phantom center, de-essing can be made more effective by compressing only the sibilant frequencies in just the mid channel. This way, cymbals that may be spread out in stereo, retain their sparkle.
But we have budgets. We have timelines.
Also, by the time you’re ready to master, you may have lost a lot of objectivity. Things you might have wanted to address early on got put aside by more urgent mix issues. You may have forgotten about it. You may have gotten used to it!
Mastering - whether I need to use something like mid side compression on your mix or not - is about offering objectivity, fresh ears, and a fresh perspective on your music.
I, as a mastering engineer, am here to watch your back.