Much like a "governor switch" that limits maximum car speed, the European Union is encouraging makers of MP3 players to implement output-volume limits in their devices.
A.P. released the story today...
Perfecting the craft of audio production; being refined by the Perfect One who made a way for us.
This past weekend during worship service rehearsal I was confronted with an audio phenomenon that didn't fully compute. The setup was fairly normal: drums, bass, guitars, piano, a few extra line-drums, 3 vocalists. The team was well into the run-through when we were confronted with a short burst of feedback in a narrow band around 3-4kHz. Immediately I looked up from my board and toward the stage to get the visual confirmation (band and vocalists wincing in unison, looking back at us in the booth like we're idiots) that something in the system just ripped through the signal chain inducing said noise-burst directly into the ear canals of all the unlucky recipients. Fortunately we (band and techies) are a team and all collectively bore the brunt of the unruly squeal. Experience immediately told me that a vocal microphone was just pointed into a monitor wedge...Although there was just one little problem: THERE WAS NO STAGE MONITOR WEDGE IN USE!!! It was, however, a little different in that it was not as full in volume as a typical feedback burst would be, so I cataloged it as an anomaly and moved on. A few minutes later it happened again. Mystified, I started scanning through all my FOH gain settings, then moved over to take a look at the gain settings in monitorland. The vocalists were collectively singing louder at that point and a few of the input channels and IEM transmitters were living in the red-zone a bit too much. So I had the monitor board operator dial back a few of the things to leave some headroom for the actual service, but didn't equate any of the changes as being related to the main issue at hand. The feedback problem didn't happen again, but after about another half-hour of mulling it over it dawned on me what might be the source of the problem. There was a particular vocalist for that service who notoriously sings quietly, putting out very little acoustic energy, thus requiring significant reinforcement from the mic and speakers. She also has a very narrow tonal range, which complicates the matter. Still, I new the feedback was not coming from the house PA as I've been able to beat her EQ up regularly enough that it's not a problem for me (note: this after frequently and lovingly encouraging her to "sing out!") and the house doesn't characteristically ring in this range if at all. This lead me back to consider the monitor setup. It dawned on me that just as I needed to turn her up in FOH, so did the monitor guy. Then I realized that the vocalist was committing the unpardonable sin of using only one earpiece of her in-ear monitor setup but with the addition of her draping the unused earpiece on the front of her shirt, hanging a third of the way down her chest...just at the same location she decided to hold her microphone while not singing!!! Who woulda' thunk!?! Feedback issues with IEMs... Her vocal was SO cranked in her mix that when her microphone passed by the open earbud, catching it at just the right angle, it caused the system to spiral into unstable audio territory! Crazy... One for the books for sure.