In the world of sound reinforcement it’s very common to see the FOH (Front of House) engineer as well as the guest engineers who mix individual artists at festivals or multi-artist event to automatically request, sometimes even demand to mix in stereo. This article looks at when and where stereo is appropriate, and when it’s absolutely not.
The FOH mix engineer is almost always positioned in a direct line to the middle of the stage, or offset by just a few angular degrees. Therefore, he or she will hear the left, right and center (if center fill is used) much as if sitting in a studio control room. Many FOH mixing engineers are content to please themselves and go no further.
But is that the best way to serve the majority of the audience? In a very large number of situations, the answer is a resounding no.
That said, a stereo mix can indeed have certain advantages if the room geometry supports the use of stereo (more on this in a moment). Stereo sources, such as digital keyboards and some analog keyboards, produce a lush sound that is not as impressive when reproduced in mono. Ditto for dual overhead drum microphones that capture the drummer’s cymbals and the overall ambiance of the drum kit in stereo. It’s always nice to hear the tom-toms move from left to right as the drummer works his way around the kit with drum fills. And within the realm of recorded tracks, stereo is de rigueur. There are virtually no commercial mono recordings available.
The room geometry of certain venues supports the use of stereo quite well. Such rooms are deeper than they are wide and include auditoriums, concert halls and some hotel ballrooms. Also, open-air concerts in which the stage location and audience locations are established by the promoter (as opposed to accommodating existing seating plans, such as in a stadium), can make excellent use of stereo music reproduction. In conditions where all of the audience members are able to hear the left and right loudspeakers, a stereo mix can be a good thing.
For stereo to be successful it’s important that the system is arranged so that the L & R loudspeaker clusters each are wide enough to cover nearly the entire width of the audience