Why pan in live sound when it only makes the audience's experience worse?
Pan is an incredibly useful feature in recording consoles and digital audio workstations.
As you know, turning the pan control to the left puts the signal in the left loudspeaker. Turning it to the right makes the signal come out of the right loudspeaker.
If you leave the pan control dead center the signal will come out of both loudspeakers equally and appear as an 'acoustic image' directly in-between.
When you're mixing, tasteful use of the pan control can create the illusion of a band spread out on stage in front of you. There's a guitarist on the left, another on the right, drums with a certain apparent width, singer and bass dead center.
You can do the same in live sound. Bear in mind however that in a small venue there is less control because the backline contributes significantly to the overall level. But let's imagine a large venue where this is less of a problem.
So there you are behind the mixing console, with the band on stage ready for the sound check.
It doesn't take a lot of imagination to decide to pan the instruments to correspond to their actual positions on the stage.
After two or three songs the mix starts to take shape and it sounds great. Time to bask in the glory of your achievement.
The sound seems good to you. But what about the audience? Is it good for them?
One thing that it is essential to remember is that as a live sound engineer, you have the best seat in the house, from an audio point of view.
It is very tempting to optimize for what you hear, but a large proportion of the audience doesn't hear it in anything like the same way as you do.
Imagine that you are in the audience, quite close to the stage on the left side of the auditorium. There's a guitarist on the stage over on the right.
If the engineer has panned the sound of that guitar to match the player's position on stage, then it will come predominantly from the right loudspeaker stack.
So from your listening position in the left of the auditorium, you don't hear much of it. In fact, the balance of the instruments seems entirely wrong, because you are only hearing one side of the stereo image.
For this reason therefore it is important for a live sound engineer to consider pan very carefully.
He or she could decide to optimize the sound for the people in the best seats in the house. Or compromise and give everyone at least decent sound quality.
Very often this will mean reining in the pan. You could go all the way to mono, or create a narrow stereo image that will sound quite good to those in the audience sitting centrally, and still be OK for people sitting towards the edges.
It is well worth remembering that live sound isn't studio sound. There are similarities, but the areas where they differ are vitally important too.