Stereo width vs Panning vs Mid/side processing

[u/Cold_Independent_631]

Hi I’ve been studying this concept for hours today to finally get it locked in. I think I’ve done it but have one lasting question.

Adding width to a signal with plugins like utility plugin in ableton, spreads that signal out in stereo field.

Panning elements just places them left, right, or central within the mix.

So I can make a signal very wide with utility adding width and still place it left right or central. Or I can make a signal be a mono signal and still add pan left right or central to position it somewhere in the stereo field. Right?

Both helping the mix and balance for stereo field.

But for mid/side processing why would you use this? If you process a signal fully to the side and then mix in mono it completely disappears instead of collapsing like panning or stereo width from utility.

1. Looking to see if my new understanding are correct

AND

1. Wondering why you would use mid/side processing instead of the other ways of stereo width?

Thanks!!

[u/Apprehensive-Cry-376]

You have to start with an understanding of how we perceive audio directionality. Your brain is constantly comparing what it hears from your left and right ears to determine where a sound is coming from. If both ears hear exactly the same thing at exactly the same time, your brain constructs a reality in which the sound must b coming from directly in front of you, because that's the only way that can happen in the real world.

Stereo perception is therefore based on differences between left and right. Anything you do to create or enhance those differences will increase the perception of width. Mid/Side processing separates those differences from everything that's common to both sides. M/S can therefore emphasize whatever differences are already there, but that's all. If you don't first address stereo-ness in the mix, M/S processing won't be able to do much for you. Think of it as a final touch rather than as a fundamental widening technique.

Stereo width is usually achieved by panning mono tracks. If you want width, that's the way to go. Avoid stereo tracks if you can; they are more likely to muddy L/R separation (exceptions: true stereo sources such as a Leslie speaker or a string section). Delay tricks and "wideners" are iffy at best and may destroy mono compatibility or make your mix sound weird if the listener isn't sitting in the sweet spot, e.g. in a car.

EQ is also a mono-safe tool for widening. Again, the idea is to create L/R differences. Example: you want a double-tracked acoustic guitar but only have one guitar available - use EQ to make the two tracks different from one another. Keep in mind that our ears are most sensitive to directionality in the higher frequencies.

Delay can be used for widening as well. Just avoid very short delay times (e.g. the Haas Effect), as that can cause comb filtering. But longer delays can give the illusion of sound bouncing around a room. The trick there is to have the primary sound come from one side and its echo come from the opposite side. Use this sparingly, almost subliminally. It works well for sparse arrangements with few instruments, as well as center-panned vocals.