Redesigning trunk, sound deadener questions

[CadillacMatt 10+ year member]

Hey guys. I'm thinking of stripping the stock grey fabric out of the trunk and laying in some carpet all around to match the interior. I am going to wrap the box I've built with the same carpet. However, since it seems like an extremely popular topic here (I've never used it) I'm thinking of deadening the trunk while it's gutted (I was looking at Second Skin Audio).

I'm mainly trying to get rid of trunk rattle with the new system, as my car is pretty quiet already as it is. Would Damplifier Pro be a good solution? If so, would I need more than one layer? They have so many different kinds out there I don't want to get something that will absorb all of the bass but rather deflect it away from the metal panels.

I'm reading up on the Sound Deadener Showdown website as well as I'm really trying to learn about this stuff, thanks! //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

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[James Bang 5,000+ posts]

I don't think damplifier is made to absorb or deflect sound. It's made to decrease/stop resonance of what they are applied to.

 

[CadillacMatt 10+ year member]

I don't think damplifier is made to absorb or deflect sound. It's made to decrease/stop resonance of what they are applied to.

I understand that acoustical energy is wasted when it flexes metal, being transformed into mechanical energy. If I can prevent the panels from flexing it should theoretically allow more bass in the cabin?

 

[Tehgregzor 10+ year member]

Yes, that is true.

 

[CadillacMatt 10+ year member]

Ok, I've heard some great things about Second Skin, I think I'll spend the extra $$$ and spring for the Damplifier Pro.

 

[CadillacMatt 10+ year member]

BTW - will thicker carpet absorb more sound? Or would it not be noticeable? //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

I plan on laying SSA Damplifier Pro all along the trunk/sides/lid and covering it with carpet

edit - Basically I'm deciding between a thin, cheap carpet like the one here at JC Whitney, or a thicker carpet that's a better quality like the cutpile found here.

 

[CadillacMatt 10+ year member]

bump and another Q...

After searching through some posts I've heard differing opinions on trunk deadening... would one layer of Damplifier Pro be sufficient, or would I need more? As I said I'm going to be putting a layer of carpet on top as well. Thanks!

 

[CadillacMatt 10+ year member]

One last bump before bed //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

 

[James Bang 5,000+ posts]

the more the merrier.

about the carpet, you wouldn't be able to tell the diff.

 

[stalin '08 10+ year member]

i once had a lac like yours. i ended up putting 175 sq ft in the trunk. i also spent two days doing it. i just wish i would of bought thicker and had used more liquid deadner. but those lac trunks ****, trap lots of the bass in, i had to take out the armrest, cut the triangle out and still wasnt satisfied, almost as bad as a bmw 3 series trunk. good luck and i hope your gonna use at least 2 15's

 

[Rudy 10+ year member]

One layer of Damplifier Pro in a trunk should be plenty - it's really designed to do the job with only one layer. For rattles, you should really try to identify the source and treat them beforehand - tighten things down, wrap wires in foam tape, stuff foam between objects that are still loose or use silicone caulk to immobilize them. Carpet is not going to play a significant acoustical role in a trunk.

 

[CadillacMatt 10+ year member]

i once had a lac like yours. i ended up putting 175 sq ft in the trunk.

//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

That ish must've added a couple hundred pounds!

but those lac trunks ****' date=' trap lots of the bass in, i had to take out the armrest, cut the triangle out and still wasnt satisfied, almost as bad as a bmw 3 series trunk. good luck and i hope your gonna use at least 2 15's[/quote']

My rear bench seats sit about 2 inches away from the back because the studs are broken so the bass still gets through (however, when people are sittin back there I get almost NO bass up front //content.invisioncic.com/y282845/emoticons/verymad.gif.3f39c5c2fd57527b671fad3efdfac756.gif) I pulled the deco cover and insulating board from the back of the seats as well. I also plan on building a custom rear deck complete with center port. And yes I will be running two 15's //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

One layer of Damplifier Pro in a trunk should be plenty - it's really designed to do the job with only one layer. For rattles, you should really try to identify the source and treat them beforehand - tighten things down, wrap wires in foam tape, stuff foam between objects that are still loose or use silicone caulk to immobilize them.

First of all thanks I read up a lot on your site (SDS is your site right? lol!). And even on the flimsier areas of the trunk one layer would be enough? I just wanna make sure because I'm going to be bonding the carpet directly to the damping mat so it's kinda one shot //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif.

Carpet is not going to play a significant acoustical role in a trunk.

Even if it's a little thick?

Thanks again for the help guys. This is a hands-on, on-he-fly sort of training for me //content.invisioncic.com/y282845/emoticons/veryhappy.gif.fec4fed33b4a1279cf10bdd45a039dae.gif

 

[Rudy 10+ year member]

First of all thanks I read up a lot on your site (SDS is your site right? lol!). And even on the flimsier areas of the trunk one layer would be enough? I just wanna make sure because I'm going to be bonding the carpet directly to the damping mat so it's kinda one shot //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif.

Can't guarantee that it will be enough - but I'd be surprised if it isn't. You'll be able to tell before you have to glue the carpet down.

Even if it's a little thick?

Slight differences in thickness aren't going to make much difference. It can only absorb very high frequencies and the difference shouldn't be audible in the trunk.

 

[FoxPro5 5,000+ posts]

If you're already going with DP, put some LLP in your cart while you're there. You'll thank me later. No use spending extra money on thicker carpet that won't do what you're hoping it will.

 

[CadillacMatt 10+ year member]

If you're already going with DP, put some LLP in your cart while you're there. You'll thank me later. No use spending extra money on thicker carpet that won't do what you're hoping it will.

I'm reading that LLP is an acoustic foam, meant to absorb sound... would that not absorb an appreciable amount of bass from the trunk? //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif