When people are testing audio stuff at concerts, what causes that sudden deafening “flare” of noise? (Hard to put in words)
Do you mean audio feedback? It’s caused when a mic picks up audio from the speakers and the gain is large enough that it re-amplifies itself and goes out of control.
Ah yes that, thanks.
The word I use is SQUEAL!
Well, in this instance, it wasn’t the squeal though. It was a sudden increase in acoustic vibration, in such a way that it made your whole body (and especially the gut) just have this uncomfortable “resonance” vibration flutter inside. Very potent.
I’ve heard that called whalesong. Our audio system was being tested to its limit and nobody was allowed in the theater/meeting room, but we could hear it from the control room (probably the whole building).