Confused about pan laws

Here are a couple of references to it for starters:

http://en.wikipedia.org/wiki/Pan_law

http://en.wikipedia.org/wiki/Panning_(audio)

Firstly in terms of your own work on your own DAW. You will find some DAW's offer different panning laws. Try moving a signal from far left through centre over to far right and select different panning laws each time. You are going to find that some of them are going to drop the signal down only down by so much when in the centre and other laws will drop the signal further when in the middle position. It is a matter of which you prefer to use.

And yes once a signal is panned (and left alone) you are going to reset its level no matter what so in the end it will end up at the right level anyway so yes you are right. But if you are wanting to sweep (eg automate) a signal right from far left to far right in a mixer move then you might be in a position to want to change the pan laws. eg you might find that if you have a pan law set for say -6 db in the centre and you do a sweep you might feel the signal is getting a little low in the centre and back up again over towards the right. So in this case you might want to try a -4.5 db pan law or even a -3 db pan law.

Also if you do pan something to a position and leave it there (eg centre for example) and you set the level OK it is when you export a session to another DAW then this might be an issue. You might have your pan law set to say - 3db and in the centre you will fine tune your level. But in my DAW my pan law might be set for -6 dB instead. So if I set that sound in the centre and set its fader correctly (same as yours) then it might still sound a little soft because my pan law is not the same as yours. So if you are planning to give files to someone else to set up in their DAW and you are instructing where the panning and fader level are, you might want to include what pan law you were using so the other person will get the correct level especially in the centre by setting their pan laws to agree with yours.

Hope that helps.

You're right, Rod. Pan laws are pretty much irrelevant unless you need to automate panning (as well as a few other, more esoteric scenarios). For the most part, you'll set your pan positions by ear and it'll sound like you want it regardless of what pan law is in effect.

The whole reason pan laws exist in the first place is they are intended to compensate for volume changes as you adjust the panning on a track. When a track is panned center, identical sounds are coming out of both speakers; they add together such that the combined sound is louder than either individual speaker. If you then move a track from the center to one side, it'll drop in volume. The default pan law (0db center) boosts the signal as you pan away from the center so that the volume stays constant. It's really just a convenience.

The pan law will be more significant as soon as you start automating pans. For example, if you put an autopanner plugin or a pan automation envelope on a track that shifts the audio from left to right, then you'll want the pan law to keep that track's level constant and avoid volume changes.

EDIT: another scenario wherein pan laws become very significant is if you foolishly change a pan law in a finished or near-finished mix. That will seriously mess up your mix! Choose a pan law once, at the beginning of the project, and don't change it.