[Doug67]

I bought what should be enough for my Mustang and F150, and installed it in the F150 Saturday (along with some new carpet which looks fantastic and makes the truck smell new /forums/images/icons/smile.gif). Since my truck is a manual, there's still the 6-inch-by-6-inch hole in the floor where plenty of sound gets through. I installed two layers on the floor Though I don't have a noise meter, the SDM seemed to help, as I had to turn my stereo up to only 15 or so to hear it clearly, as opposed to 18 or 19 before. The truck also seemed more solid, with less clunking over bumps.

SDM is very sticky, compared to Dynamat, but not as thick. Where you can peel Dynamat off somewhat and reposition it, you can't do that with SDM. It especially sticks to itself, so be careful when installing. I think the extreme stickiness may have helped tie the floor together somewhat, resulting in the feel of greater solidity. Putting some on the inside of the roof would probably help a lot, too.

Altogether, the cost was $77 for 55 or so square feet.

 

[pprince]

Cool...thanks for the info.

The SDM is not structural so it could in no way "tie" the floor togther.

 

[66candy]

Is SDM specialy designed for sound reducing ? I always wandered how this tar stuff used on roofs will work (can't find the correct English word for it right now). It's much cheaper compared to the "official" sound deadening material and it almost looks and feels the same ?

 

[stangdesign]

I did the same thing to my stang a while back (soundproofed). I used the soundproofing stuff you get at pep boys. It was non-adhesive. I ran into one problem, I lost about a 1/2 inch of pedal travel (When I pin it) Otherwise, It works awesome. I did my ceiling, firewall, trunk, and floor. Much quieter!!!

 

[kketell]

I think you will find the the SDM from www.sounddeadeningmaterial.com is pretty cost effective. I don't know what the tar paper cost is, but at $1.00 USD per square foot, SDM is pretty cheap.

 

[pprince]

100$ per square foot?

At that cost it would cost 2-3000$ dollars to do a car. Not cheap in my mind.

 

[kketell]

DOH!!!!

Make the $1.00 USD per square foot.

 

[Axnjxn]

HERE is a good article on this subject.

 

[Doug67]

I know it's not structural, so I described how it "seemed." The mental impression I got was of an adhesive connector that reduced harmonic vibration or something--I'm not a sound engineer. The truck has a more solid "thunk" when it goes over expansion joints, etc.