I just put a JL Audio W3 12" Sub in a JL Powerwedge box in the trunk of my Mustang. It is now facing backward, up against back seats. It sounds good but is making my trunk rattle like crazy. I took out the covers inside the trunk, but the deck lid is the biggest problem now. What type of sound deadening is the most effective, but not too expensive. I have heard the FATMAT works great, but are there any other options that you have heard/used and work well?
Also, Is having the sub facing the back of the car the best way to have it? I've heard that if I use a sound deadener on the trunk it will work as a second eclosure and make it much louder/clearer, is this true? Thanks for helping out a Newb like myself, its greatly appreciated!