Sound deadening really necessary?

[Rudy 10+ year member]

Deadening also changes the resonance of the vehicle. My resonance frequency has changed from the deadener that I put in my truck. Stiffening panels doesn't always help. If I brace certain parts of my truck (make them stiffer) I LOSE score.

Optimizing the vehicle's capacity to contain and resist pressure may very well change its resonant frequency. If the rest of the system isn't tuned to match the change, losing score would be the expected outcome. It's critical to approach things systematically.

 

[Lil Poot 5,000+ posts]

Deadening the cab floor in my Explorer (older model) had the greatest effect on quieting road noise. It was like driving a different vehicle with a noticeably audible difference. I didn't notice any difference when doing the doors, roof, or hatch area.

while the floor helped, my 98 explorer showed much better improvement from doing the doors roof and hatch.

 

[goodstuff 10+ year member]

What Rudy Said.

 

[SPLaudio 5,000+ posts]

in a trunk car the floor and wheel wells make a huge diff in road/exaust noise...