Trim Down Those NVH

As you drive down along the road surface, the impact of the rough surface is transferred from the tyres, through the suspension and shocks and finally into the body of the vehicle which will cause vibration. As the car motion continues, so does the energy to make the car body resonate, creating a noise floor that quickly rises to anannoying drone. A door mounted mid range speaker can cause theouter skin of the door to vibrate, which in turn causes another part of the door (inner door panel) to also resonate so on and so forth. So the best idea is to apply a sound damping material.

Research from the suppliers of these materials indicates that the single biggest reduction in noise is achieved by dampening the cars floor-pan then followes by the front firewall between the passenger and engine compartments, then the inside of the wheel arches, the door skins, the rear side body panels and finally the boot area including the lid. One should bare in mind that anything thicker than 6mm is going to make the door panel almost impossible to fit onto the door frame (at least on this car). And the after effect isn't that pronounce either.