[iclukay]

I have 2 alpine type R subwoofers with MRP-M500 mono amp, it shakes the car pretty hard and as a result causes a very loud rattling that sounds like its coming from somewhere under the rear bumper.

anyone had any similar issue or know of a fix?

thanks!

[Sarracino89]

Originally Posted by iclukay

anyone had any similar issue or know of a fix?

thanks!

Take out at least one of the 12's= problem solved.
I understand the want of 2 12's, but that was when I was 16 and drove a corolla LOL. but do you really need 2 12's? To each their own, but if I were to do 2 subs, I would run 2 8's or 2 10's IMO
if you continue to run the two of them, you may want to line the trunk with dynamatt and see if that heps.

[iclukay]

I know it's a bit overkill, but you can always turn the bass down, then turn it up for a night out with your mates, a little bass is always fun

I thought about dynamat, but I wanted to get some information first. The vibration isnt coming from the trunk, it's under the bumper. To me, it sounds like exhaust head shield rattling against the frame, but you never know.

[fdriller9]

I have one 12" type-r in a sealed enclosure and a JL 500/1. I also have this rattle. I think it comes from the compartment under my trunk floor but you have a 335 so you don't have that.

The only other thing I can think of is the vents on either side of the trunk.....ones is by the battery is by the amp/cd changer area (not sure actually, I think there is one there though).

They vent into the rear bumper I guess and it rattles the panels underneath.

[k3m0-330i]

its not the bumper its the gas door! lol

[fdriller9]

Originally Posted by k3m0-330i

its not the bumper its the gas door! lol

That rattles as well. Along with my license plate....:/

[Sarracino89]

Originally Posted by iclukay

a little bass is always fun

True true, you have me there

[cbi1972]

Originally Posted by iclukay

I know it's a bit overkill, but you can always turn the bass down, then turn it up for a night out with your mates, a little bass is always fun

I thought about dynamat, but I wanted to get some information first. The vibration isnt coming from the trunk, it's under the bumper. To me, it sounds like exhaust head shield rattling against the frame, but you never know.

There are a lot of ways to reduce the noise associated with heavy bass. If you haven't already, I would definitely recommend lining resonant metal surfaces with dynamat or similar dampening material. You can also put foam between things like trim panels that are making noise by rattling against each other.

Wherever your rattle is coming from, it can be dealt with.

I recently found the following site, which seems to be a handy guide to the various ways to deal with noise:
http://www.sounddeadenershowdown.com

I currently have a Lexus GS400 with 2 10s in a trunk that is dynamatted pretty well, and I even filled in the braces with expanding foam, but it still rattles the heck out of the rear deck and I think some trim around the trunk and back seat. I recently ordered some mass loaded vinyl and closed cell foam from him to hopefully sort it out. If it doesn't work, I may be trying out an E9x.

Exhausts get pretty hot, so if that is what is rattling, you need to choose your materials carefully. According to Don at the site I linked above, The main material in Dynamat, is good to at least 400 F. I am not sure how hot an exhaust gets, but you might try some steel wool in a gap that is rattling.

Whoever is having the license plate rattle, apply some dynamat on the back of your license plate and some closed cell foam to the back of that, and screw it securely down with 4 screws, and it shouldn't rattle any more.

[bmw325i]

I also had two type rs in the trunk running off around 1400 watts the rattles were pretty bad. For the license plate I took off the plate and the bracket and put some weatherstripping (they have it at home depot it's pretty much foam that's sticky on one side) I covered the part of the bracket that touches the trunk and the back of the plate. This works better than dynamat IMO. I then used dynamat inside the trunk which helped a little with the rattles. My final solution.... I have 1 type r in the cabin no rattles and more bass.

[VP Electricity]

Originally Posted by cbi1972

I recently found the following site, which seems to be a handy guide to the various ways to deal with noise:
http://www.sounddeadenershowdown.com

I've been recommending that site for some time. Don is a great guy.