Focus Fanatics Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
454 Posts
Discussion Starter · #1 ·
I'm running 2 OZ Audio 12" Matrix Elites with about 700 watts r.m.s. going to each in a sealed box. They get loud and rattle pretty aggressively even though the trunk, trunk lid, all 4 doors, and platform area above the rear seats are sound deadened well.

Also, I built a carpeted, MDF, platform that contours the trunk floor, so it's sturdier and absorbs the sound better.

My question is, has anyone out there experimented with isolation pads? People use them for HT applications and swear by them, so why not try in cars.

The obvious solution here is more sound deadening, but that stuff is expensive. I can make a isolation pad for around 40 bucks, and came up with a design that will keep the subwoofer securely mounted to the wood platform.

Any thoughts welcome
 

·
Registered
Joined
·
1,326 Posts
Let's not overthink this. A rattle is just two panels vibrating against each other. Shove something between them and the rattle vanishes. It doesn't have to be special "audio isolation padding" or dynamat. Cardboard is just as effective. Expanding foam is just as effective.

The point I'm trying to make is that you need to seek out the specific areas that are making noise, then just do whatever it takes to stop it. If your carpeted trunk platform is vibrating against the metal floor, then shoving cheap eggcrate foam under it will be just as effective.

The advantage dynamat has is adding weight/changing resonance. Sound isolation foams just absorb sound waves, but are generally for higher frequencies. Not nearly as effective for sub bass.
 

·
Registered
Joined
·
1,691 Posts
What brand deadener did you use? Some are just rebadged roofing tar. Doesn't do the same job, can get messy, and can stink.

Did you deaden the whole trunk?

2 cans expanding foam in the trunk lid/door can take car of a lot if trunk rattle.

The other thing to look at is ccf (closed cell foam) it reduces airborne noise and panak vibrations against other panels.

Look up second son. They have a few in depth posts about deadener.
 

·
Vince your Moderator
Joined
·
5,074 Posts
It is called decoupling and it works very well. You want to use closed cell foam(CCF).

My enclosure is decoupled from the body of the car. I have up to 3 layers of deadener inside of my car and decoupling the enclosure was the icing on the cake.

The best question from the above members is, what brand of deadener did you use?
 
1 - 4 of 4 Posts
Top