Originally posted by Shawnsim:
Alright, lets talk about feedback.
Feedback occurs when a plugged in source gets too close to its output. I.e. a guitarist gets too close to his amp when his gains and levels are pushed to the max. Feedback. Feedback occurs when a singer gets too close to the microphone when levels and gains are pushed..
To put it in a certain perspective.
The crowd was so loud that the announcer had to turn it up to 11 and fed back every time he got near the microphone.
It is not rocket science
For the crowd to produce feedback. 1. the crowd would be holding an electric device hooked up to a PA or amp and be in close proximity to it.
Come on. How likely is that.
I did not at any point say that the feedback was from the crowd. The feedback was from the crowd noise being pumped through the pa system at such a loud level that the broadcast mics were picking it up and creating a feedback loop. When you are dealing with stadium sized systems pushing thousands of watts, the mics don't have to be that close. It is a problem I have had to deal with many times in the past twenty years. The way you would ideally execute the pumping of the crowd noise is to place omnidirectional microphones away from the speakers as far as possible, then you'd gradually increase the gain structure in the matrix when you wanted that extra 10-12 db that these record setting stadiums magically produce. The part that makes me skeptical is that extra 10 or so db that cannot possibly come from human vocal chords. Otherwise the broadcast mic explanation might be feasible. But then we have that inexplicable db gain as the fly in the ointment...
Thanks for the lesson on feedback though, after mixing sound for 20+ years I was beginning to think I would NEVER figure it out.
[ Edited by Memphis9er on Dec 19, 2013 at 10:25 AM ]