I agree with ronrsr. In fact on the contracts of some bands, the ba’al simcha can check off how loud they want the music.
Music is meant to be listened to and enjoyed, and lead to being inspired–not digested by every pore in the body.
I have been to numerous chasunahs where it is very clear that the ba’al simcha wanted there to be healthy level of sound, and the dancing was so geshmak!
If you say hello to the person right next to you that you’re dancing with in the circle, and they say “what did you say?”–then the music is definitely too loud. And unenjoyable. Either that, or the other person was smart and wearing ear plugs–something more adults are doing at chasunahs.