Common Sound Problems During Live Performances and How to Troubleshoot Them in the Moment
You're three minutes from curtain. The house is full. Parents have their phones out. And then you hear it. That sound. The one that makes every theatre director's eye twitch.
Feedback.
Or maybe a mic just went silent mid-monologue. Or the lead's voice sounds like she's singing from inside a mattress. Whatever it is, it's happening now and you don't have time to call anyone. Here's what you actually do.
The Squealing Feedback Monster
Feedback is what happens when a microphone picks up sound coming out of a speaker and the two of them decide to become best friends in the worst possible way. When it happens, lower the volume on that specific mic channel first. Don't just panic-mute everything. Then figure out why it happened. Nine times out of ten, a performer walked toward a monitor or drifted off their blocking. The fix is usually positional. Your sound operator should also be ringing out the room before every show, meaning they run each mic channel and find the frequencies that want to feed back before the audience ever sits down.
The Mic That Decided to Quit
A wireless mic going dead mid-show is almost always a battery. Almost always. Start every rehearsal and every performance with fresh batteries, full stop. "It was fine at dress rehearsal" is not a battery strategy. Keep spares at the board, assign one responsible human to own this job, and have a plan for how you swap a pack during a scene change. Also worth noting: students bump that power switch more than any of us would like to admit. Check that too before assuming the worst.
Vocals That Sound Like Mashed Potatoes
If your audience can hear sound but can't understand words, something has gone wrong with either placement or EQ. A mic that slipped under a costume is the usual suspect. Always do a full check with performers speaking at actual performance volume, not the polite whisper they use when they're "testing." If the EQ hasn't been tuned for your room, try boosting slightly in the 2kHz to 5kHz range. That's where vocal presence and intelligibility live and it makes a surprising difference.
The Room Where Half the Seats Sound Great and Half Don't
Uneven coverage is usually a speaker placement issue and you probably can't fully solve it on show night. What you can do is make sure your performers are staying in their blocking. A performer who wanders off their mark will fall out of their mic's sweet spot and the back half of the house will lose them entirely. Keep them where they're supposed to be and your sound op will love you for it.
The Mic That Was Perfect at Rehearsal and Then Wasn't
Costumes. It's always costumes. A mic pack that sat perfectly in a t-shirt during rehearsal behaves completely differently stuffed into a period corset or a three-piece suit. Always do a full dress rehearsal in complete costume and have your sound operator reset every single level from scratch during that rehearsal. Not the week before. That rehearsal.
The shows that fall apart are almost never the ones with bad equipment. They're the ones where someone said "we already checked that." Build a pre-show checklist and run it every single time without exception. Future you will be very grateful.