Hi, sorry if this has been posted before, but today i changed de door panels and when i opened them i realize there was a little like cousion or sponge like thing, and i wonder, can i fill all that space with some material to help reduce exterior noise? thanks

 

You can use soundproofing materials like dynamat on the door, floor, roof, hood, and trunk to reduce outside and engine noise while improving audio quality at higher volume

 

+1 to Dynamat, as long as you don't care about the extra few pounds.
I'll be doing about 90 sq ft in my evo. Already installed about 50sq ft so far, and my last car (nissan maxima) had even more. It's not rocket science - if you can take apart your car you can do sound deadening. Everyone complains about the added weight, but it's probably 40lbs or so --- but its sprung weight, so that will really make VERY little difference.

Just buy quality product - down here in FL, half of the brands fall off in the summer heat.

 

 

^ There's sometimes a lot of BS on FloridaSPL but that's actually quite a good video.
He's dead on about the differences between a traditional dynamat being a vibration and resonance material versus the mass-loaded vinyl meant for being a sound barrier.

The bummer about the second skin product is that it's no longer foam-backed, which is needed for the MLV products. Cascade VB-3 is my choice. My wallet couldn't do MLV right now but I'd still like to add it on at some point; 72 sq ft of dynamat extreme was $278 shipped to my door, and I couldn't do MLV on top of that right now.

 

P.S. This is a fantastic read, if you have 5 minutes to understand the differences between the different types of sound deadening.

http://www.cascadeaudio.com/blog/tre...road_noise.htm