I've noticed that certain bass frequencies make the plastic rain sheeting inside of my door resonate and rattle(it's not the metal door itself just the plastic rain sheeting). So I'm contemplating buying one of those Dynamat kits specifically just for speakers. Has anyone had any experience with just matting the area of the door around the speakers? Did it improve the sound quality much? Do you think I'd be better off matting the whole door? Also, does anyone know of a place where I can get a good deal on Dynamat, Raammat or the equivalent? Oh and does Dynamat Xtreme warrant the extra price over regular dynamat? Is it that much of an improvement? Finally, did you put the plastic sheeting back on inside of the door after applying the mat? I'm afraid that if I didn't I'd have a problem with water getting inside of the car. Thanks for any info.