Although I basically understand compression I was wondering if there were any "rules of thumb" for compressing the audio for things like school plays that have music ?
Something like 2:1 or 3:1 ratio at -12 threshold with an attack of 25-50 miliseconds or 3:1
or 4:1 at -6 threshold. I plan to normalize the audio first.
There are no hard and fast rules when it comes to sound compression.
I would suggest lower compression levels. The object is to make the sound legible. In a school play, I assume that the mikes will be on the stage and that the performers would walk up to the mike to sing.
As this is kids, the mike technique might be missing so the compression will help to throttle down if someone gets very loud in the mike.
Use your ears during the sound check. That is the best way, but again, use moderate compression. The documentation to your compressor would have some suggested settings.