DIY Sound deadening?

Would it be at all possible to take foam exercise pads and/or foam bed egg crates and put them in the door panel as a sound deadening alternative to dynamat?
I've been using both the foam pads and the egg crates as sound proofing for my basement where my brother and I play drums and guitar. It made a huge improvement in sound quality and the punchy-ness of his drums. I don't know if it would do the same in a car though, or that it's even safe (seeing as it's around wires and stuff). I'm not an expert on car audio, but it seems like it would make an improvement in bass response and help keep outside noise from getting in.

Anyone tried this in the past or have some insight?

That is not sound dampening, it's sound absorption. It does work to absorb road noise, rattles and rear sound waves of the speaker, but it does not do what Dynamat or other sound dampening does. If you want to gain some functions of a Dynamat type product you will need to add mass to the door panels, specifically parts that are mostly flat (not panels that have lots of bends or are bolted to other panels because they are already less likely to flex or vibrate). The other use for Dynamat is to seal over openings/air holes in a door to create a more sealed door to capture rear waves and improve speaker response.

schmiddr2 said:

That is not sound dampening, it's sound absorption. It does work to absorb road noise, rattles and rear sound waves of the speaker, but it does not do what Dynamat or other sound dampening does. If you want to gain some functions of a Dynamat type product you will need to add mass to the door panels, specifically parts that are mostly flat (not panels that have lots of bends or are bolted to other panels because they are already less likely to flex or vibrate). The other use for Dynamat is to seal over openings/air holes in a door to create a more sealed door to capture rear waves and improve speaker response.

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So basically if I were to put these in my door it would help with road noise and not really improve or decrease my audio quality?

All sound that is not original to the recording can be considered distortion. So will it absorb some of that, probably; is it worth the effort, I don't know. I assume this is closed cell foam, if so there is some good info, here ---> http://www.sounddeadenershowdown.com/products/ccf

EDIT: here is some more reading ---> https://www.google.com/search?q=exe...qs=chrome.0.57.13433&sourceid=chrome&ie=UTF-8

Could do what my brother did, he sprayed this stuff on his floors, quarters, doors that's similar to lizard skin sound dampening and then put down the same material as yoga mats. All you hear now is a loud "thud" when knocking on the metal.

use fiberfill aka pillow stuffing. the thicker the better. you can get it hobby lobby. hot glue it to the back side of the door panel.

Why not just get dynamat?

like this

BlkCurrantKord said:

Could do what my brother did, he sprayed this stuff on his floors, quarters, doors that's similar to lizard skin sound dampening and then put down the same material as yoga mats. All you hear now is a loud "thud" when knocking on the metal.

Click to expand...

This will really block out road noise, etc. I think there was a post/link on here about someone who went to this extent to complete block any road noise. They gutted the interior, sprayed some type of liner as well as added sound deadening material. Made the car alot heavier, but it depends on what your priorities are.

im currently sound deadneing my doors. i know it is not ideal and there are people out there with many mixed feelings, but im using peel and seal. its 17 bucks for a roll at lowes and its basically generic dynamat. i layed it on the inside on the outer most sheet of metal and when i knock on it it gives that deeper sound instead of a pingy sound. i used my hand to move the metal around and if it had alot of play or pingy sound when tapped, i would add a strip of the peel and seal to give it that extra thickness. i took off the nasty pastic white sheet that was over the door before i did ll this and now that im finishing up the door, im using sheets of it to put back over the openings where i put the peel and seal on the inside. basically im trying to cover as much surface area on the inside, both on the outside sheet metal and the inside piece where the speaker is attached to. now im starting to cover up the holes to create a "sealed box" type of effect. EDIT: make sure you dont cover up the holes for the door panels, i wasnt paying attention and i accidentally laid a sheet over. simply fix all i had to do was punch a screw driver thru but still pay attention lol


my panels are still off and looking at that polyfil, its really making me want to do it. i also saw a thread where someone put foam strips around the door so when u slam it, there is no metal on metal sound. ill have to find that.


just a thought if you dont want to dish out big $$ for sound deadening. youtube "peel and seal sound deadener" and look into it. i personally have never had ANY issues with a rubber or asphalt smell, even in the California heat. had it in my trunk for over a year, no issues of drooping sheets or bad smell. just giving u options