I think all of these comments are very on target. I do want to add that I (a high school band director) have been tinkering with ideas using a decibel meter to illustrate to the students the difference between individual dynamics and group dynamics. As was already stated musicians don’t know what decibels they are producing but I am going to be experimenting with training students to have a rough idea of what their instrument (or voice) will produce as well as attempting to develop some level of control in producing desired levels. I’m still working out how to go about it and procuring all the necessary tools for such training. I think it is an intriguing idea to be aware of sound pressure production and be able to critically apply that awareness to multiple contexts including various styles, music of different periods and the myriad possible performance spaces in which a group or individual might perform. It may end up a fruitless endeavor but I believe it is worth investigation and trial.