In the rear deck of my car, I want to seal the 6x9s from the trunk to 1. To increase power-handling, and 2. most importantly, to avoid blowing the speakers due to the pressure of my 12" infinitys. The way the rear sheet metal is in my car, (90 bonneville) it would be a bit difficult to seal them off 100%. I am looking at DYI install only. There is a plastic cover that screws onto the underside of the deck. Would it be possible if I packed the back of the deck with this insulation? Before you laugh, I think it would work because it would dampen the speakers and would have the effect of stuffing a sub box. I've heard of somethig like this it was called an aperiodic membrane. Am I just hallucinating, or could this actually work?