has anyone tried any of this material in a car for sound absorbsion? it should be much more effective than flat foams.

 

so no comments on this? i was going to try this in my trunk (out of view).

 

Try it, I used to use a product called Bassline which was a plate of this stuff about 5x12", it worked great. We glued it on with spray adhesive and screwed it on as well. Definitely made the box sound way different.

 

I've used it in boxes for a while....I get the eggcrate version (about 2" thick) for free at work, which I like....

It disperses the back wave and cuts down on standing waves inside....there is a definite difference to the sound and it's an easy way to change the enclosure volume if you're trying to change it's frequency response.


I'm not sure what you're trying to do with it in the trunk.....it's not heavy enough to keep it from vibrating, getting rid of more vibrations requires mass, and Dynamat type products seem to work best for that. Spray foam in between the layers of metal will stop them from bouncing off each other.............doing both will take care of a lot of it......

Besides, a trunk lined with the egg-crate foam would look pretty wierd if someone wanted to see what's in your trunk......

Hmmm, I wonder if some neon would help......

HTH

 

actually i was thinking more for sound absorbsion than for the sub box. i've seen 3 sided phone booths with wedge foam used on the floor in noisy factories and the amount of outside sound absorbsion/dispersion was impressive.

the car is already deadened but i'm looking for a bit more road/exhaust noise isolation now. since the car isn't a hatch no one is going to look in the trunk that often. also, it did occur to me that this will likely muffle the sound from the sub a bit but i should be able to turn up the volume a bit to compensate.

 

Was that way different in a good way?

 

what were your thoughts on the sound BR? Was it tighter? cleaner? better attack?

 

Foam as a whole is a fairly (no where near as good as 3M thinsulate blankets or fiberglass blankets) effective sound absorber above 1000 Hz. To have significant affect on lower frequencies you will need 2+ inches of foam. for significant attenuation of sub bass you would need almost 6 inches. for stopping reflections and cutting down ambient HF foam is a great material. the heavier the foam the more effective it will be at lower frequencies the lighter the better at high frequencies. for sound room and general sound absorption the egg crate style is more effective due to more surface area exposed to sound.

 

Yes to all 3.....The first box I tried it in was a little too big for the subs I used as replacements for 2 casualties years ago.....it was easy to figure out how much air space the foam was going to take up and I have built sealed boxes since then allowing for a layer of it in volume calculations.....I think the shape of the surface does a great job on the back wave by bouncing it in all directions at once....maybe just to my ears but there ya go.....

 

I'm using foam under the grill covers on my dash. 6 different types. I had to test to find what worked best for me, but the difference is night and day if you remove it.