i took out all of the factory crap then used dynomat in my car. cut out the road noise and def improved the sound quality of the car. floor and sides trunk to firewall both portions of the door and the roof. i did use some other materials for behind the speakers to help dampen the vibrations in the door.

 

here you all go a good video about sound

 

^^^ Typical car audio ignorance. While there are grains of truth in the vid, the overall thrust is simply uneducated. Didn't I post a link explaining how all this works earlier in the thread?

 

Hey FJF, quick question. I know i'm reviving an old post, but have you put MLV on the door? I get a feeling that it'll be too thick to fit in between the metal and the panel. Thanks