Originally Posted By: BuickGN
How much of a difference in sound did you see?
EDead is great stuff; I have used their mat type products and their liquid products in the past with great success.
Dampers, such as pictured above, add mass to the object they are attached too. The object with mass loading is to lower the resonant frequency, thereby reducing the odd rattles and squeaks. These damper type products are not really intended to block or muffle road noise, though they do help.
To block road noise, you’re going to want to use a product designed to convert sound waves (pressure waves) into heat. There are several fiber and foam products on the market that do this, many of them are composite materials...consisting of a foam primary layer, with a heavy vinyl backing to further block sound. These can be pretty pricey, so a decent cheap alternative is carpet pad...which is really a combination of open and closed cell foam.
That said, damping products make a car feel more "solid"...and that is desirable to many people. The way I describe it, is a damper will make your car feel German and really helps on rough roads at low speeds. Noise blocking products will help with highway noise, and will muffle high speed wheel and wind noise better.
That said a good deal of your ultimate success depends on what kind of car you started with. Cheaper cars typically use thinner glass....and the windows on a car are the primary conduits for noise. You’re never going to get a metro to be as quiet as a Benz, though you will improve the metro with the right products.
I have a Ford Focus, and about 4 years ago I installed roughly 140sqft of damping material (all Edead), and roughly 60sqft of noise blocking material (foam pad). The end result was a rather solid economy car...much more solid feeling than any compact I have been in to date. It also has absolutely no rattles, even with a big stereo. That said there is still pronounced tire and wind noise at 80mph, less than stock, but still more than a luxury car. The limiting factor on the Focus, as I would suspect on many other cars, is the glass quality.