Mixer Pan L/R Balance

Pan law and mixer balance

Pan a mono signal to one side of a stereo bus and you have to attenuate it at the center, otherwise it jumps 3-6 dB louder than it would at a hard-panned position. That attenuation is the pan law. The values you'll run into are -3 dB (cinema/equal-power, which keeps perceived center loudness right in stereo), -4.5 dB (a compromise, default in many DAWs), and -6 dB (broadcast/equal-amplitude, the safest for mono compatibility, since L+R at center sums to 0 dB). At the extremes the signal sits in one channel only; dead center, it splits across both. So pan=0 under a -3 dB law gives L=R=0.707, while pan=+100 gives L=0, R=1.

Applications

You'll find it in studio audio mixing, where every DAW (Logic, Pro Tools, Ableton) exposes pan law as a project setting. It also matters on FOH live consoles, analog and digital alike, from the Behringer X32 to the Yamaha CL. In broadcast it's a real concern because mono compatibility still has to hold up for AM radio and old TVs. And in cinema, Dolby and DTS rely on equal-power panning across L-C-R-Ls-Rs.

FAQ

Which pan law should I use? Go -3 dB for music heard in headphones or stereo. Pick -6 dB if the mix might get summed to mono, like AM radio or a phone speaker. If you're unsure, -4.5 dB is a safe middle ground.

What's the difference between pan and balance? Pan spreads a mono source across L and R. Balance, by contrast, just attenuates one channel of a signal that's already stereo, with no crosstalk between them.

Why does the center sound louder without pan law? When a source is centered, L and R sum together, acoustically if they're uncorrelated or coherently if it's mono. That summing adds 3-6 dB at the center compared with a hard-panned position.

Does pan law affect the master fader? It doesn't. Pan law only touches how panning works inside the tracks; the master just scales the stereo bus.