Hey Im looking for a DIY Audio Fix. I have a custom sub box sealed (and facing into the car) with 2-12" Alpine Type R's and a JBL AMP. The trunk is obviously shaking and rattling and I am looking for a fix. I would really rather not spend a ton of money on a Dynamat. Any ideas?

Lots of varieties of soundproofing will help change the characteristics of the trunk. My buddy has a place down here that sells thin soundproofing mats that you could essentially glue to your trunk so that it didn't resonate....I'm sure there are similar suppliers around your town.

I'd have to look more into it, but try looking up places that do soundproofing for other applications other than audio. Dynamat is a ripoff.

Yeah, there are lots of similar products to Dynamat (Hush Mat, Brown Bread, etc). However, with dual 12s you will have buzz and rattle unless you fill the car with concrete.

Let me put this in perspective: I've DJ'd school dances with the amount of power you're running in your TRUNK. You can pile the deadener on there but it's still going to be noisy when you crank it. My advice is to get yourself a less intense rig. That's just nuts.

Yeah, there are lots of similar products to Dynamat (Hush Mat, Brown Bread, etc). However, with dual 12s you will have buzz and rattle unless you fill the car with concrete.

Let me put this in perspective: I've DJ'd school dances with the amount of power you're running in your TRUNK. You can pile the deadener on there but it's still going to be noisy when you crank it. My advice is to get yourself a less intense rig. That's just nuts.

He does have a lot of power thumping back there...but it would help to change the natural frequency of the arse end and reduce the rattles. I would imagine that with the two 12s that it's more than just the trunk rattling...

I know lots of cars pack the deadening material in every crevice to reduce the rattle...but I'm not sure what extreme you'd want to go to.

hahhaha SHE does have a lot back there... its pretty loud. My brother custom designed the box and put it in for me. Its a sick setup. I assume reducing down to 1-12" would be a lot better then? Thanks for the input

Well, 1 12" would reduce the level. It's a tiny car, so running a thousand watts of subs is overkill! I wouldn't say a little dampening would hurt, but these cars are pretty well damped already. You'd be putting in some MAJOR work to work out the rest of the rattles. You can start by pulling off all your panels and using BLACK GAFFER TAPE (most music stores will have it) to tape down any wire looms. Gaffer tape is a fabric tape like the stuff that's already in your car, and it doesn't break down like duct-tape glue does. That should help, but you need to be very thorough.

I'd also try removing the tool case, stuff in your glove box, anything not tied down. Listen for where the rattles are coming from. Body panels might be loose; the exhaust might be loose; the catalytic converters rattle like hell on these things. Your trunk mat will vibrate too, try using some velcro on it.

And then, after you've done all that scort says...you take a crane and dip it into a giant vat of tar. Problems solved...

Seriously though, I have one 12" in my trunk and it still farts at the people behind me. It's mainly the rear deck and trunk lid that vibrates for me, it's just that there's too many other things that are wrong with my ca for me to worry. So, basically, even with one of those subs, you still may run into problems...

I had a good listen to it, and inside the car is sounds wicked good, its just the trunk that vibrates to all hell. I have no tools in that kit so we are ok. When the trunk is open it sounds great.

Put some dampener and some foam weatherstripping on the back of your licence plate. Otherwise, not much more you can do.

Put some dampener and some foam weatherstripping on the back of your licence plate. Otherwise, not much more you can do.

Did that for mine, doesn't do much. It's the actual trunk that wants to vibe off your car...it's almost unavoidable with that much woof in the back.

Bummer... I guess i will have to tune her down a bit...