Here is a very nice video showing off a friends use of second skin sound deadener to increase the bass in his door panels.
Sound deadening door panels for more midbass.
Soundproofing rubber is typically a dense form of neoprene the same stuff they use in wetsuits to insulate against the cold.
Lift the protection under the door panel.
More buying choices.
Dekiru upgraded 12 pack acoustic panels 12 x 12 x 0 4 inches sound proofing studio foam padding high density bevled edge tiles soundproofing panels great for wall decoration and acoustic treatment 4 1 out of 5 stars 500.
Check it out here edited january 13 2015 by second skin.
If sound can leak around the sides of your door consider adding soundproofing rubber to the perimeter.
On older cars they were simple plastic wraps while on newer ones the protection is also somewhat sound deadening since it s made of foam or fiber materials.
Most cars have another layer of protection under the door panels.
Use a high quality sound deadening damping material and place it inside the outer sheet metal layer of each door or quarter panel.
Sound absorbing acoustic insulation wall panels 2 pack model 02520 view the owens corning sound absorbing acoustic panels.
Owens corning paintable white fabric square 48 in.
Use wood screws to attach the plywood to the door.
Dynamat 10435 12 x 36 x 0 067 thick self adhesive sound deadener with xtreme door kit.
Deaden the outer sheet metal of the doors.