Is there a cheap alternative to dynomat? I've been told before that tar roofing covering will do the job, just stink for a while(also told Dynomat can do that too). My Saturn is like a cardboard box with speakers in it. Might as well not be a shell. People hear my radio as loud as I do from 20 feet away. It would simply cost me too much to dynomat a 4 door car and the trunk, and if I get ambitious the roof or some other stuff. It would blow my budget for new speakers(which it needs since anything about 30 volume or 00 bass it crackles.