Phase coherence for live sound

The phase problems you fight in a mix don’t disappear on stage. A live kit, a guitar cab with two mics, a leslie top and bottom, a pair on a grand — they all comb filter through the PA the same way they do in the box. What changes live is the budget. In the studio you can spend a few milliseconds of latency to line signals up. Through a live console feeding wedges and a PA, you usually can’t.

Two corrections, two budgets

This is where keeping phase coherence and time alignment separate matters most.

• Phase Coherence correction works on the frequency-dependent relationship between mics without sliding anything in time. Because it isn’t buying its result with a bulk delay, it’s the part of the job suited to a live path. PhaseLock is designed to apply it without adding latency. Verify that on your own console and host before you rely on it, since live rigs and plugin hosts vary.
• Time Alignment buys its result with delay: it moves a signal to line up the transients, and that delay is exactly what you’re trying not to add on stage. It’s a real tool live, but only where you can accept the latency it introduces, such as aligning a subline to the mains.

Built for the host

PhaseLock performs this correction in real time inside a compatible plugin host. For a live rig, test the complete signal path and confirm its latency and stability before relying on it during a show.

Audio demo to add: a multi-mic source through a live-style chain, before and after phase coherence correction — level-matched, with a short methods note.

Trust the room

Live, your reference is the PA and the room, not a meter. Make the correction, walk the space, and listen for the low end and the punch returning without the mix smearing. As everywhere else, some phase interaction is part of a big live sound. Fix what’s costing you weight and definition, and leave the rest to the room.