MrGraphics

I've been pretty happy with my stereo system for a while, but have not been happy with the car noise in general. I've Dynamated EVERYTHING but the road noise in the Z is just loud. It also seems to rob the mid lows away from the music.

On a tip from another board, I went out and bought a 6ft x 6ft piece of jute - or 40 oz fiber carpet underlayment for those of you not familiar with the term. I put some in the easily accessible areas of the trunk (under the spare), in the doors, and under the seats. MY GOODNESS - the car is almost as quiet as my BMW. I'm going to get another 6 x 2 piece and dismantle the trunk and also install it in the storage areas. It should be whisper quiet afterwards.

The concept is, the tiny fibers in random directions act to break up the road noise and dissipate it.

One note about jute, you can't put it where it will get wet (mold). Luckily, since I've dynamated it (fake dynamat for $50 from a roofing supply company) everything is sealed, so no water.

SQ is so much better now, and I don't have to play my music so loud (save my hearing).

Best of all -the jute cost $11 and added maybe 10 lbs to the car.

Z BOY

iTrader: (41)

so where can jute be purchased, and how much does it cost?

zmespeed

tell me tell me. sounds so easy and my car is already totaly apart....interior wise

35oZephyR

iTrader: (4)

Don't want to go off on too much of a tangent but I think one of the KEY sweet spots in the Z that's letting in alot of road noise is under the seats.

Last week I took out the seats to have the leather re-dyed. I left the passenger seat out to dry while the driver seat was in, then drove it around for a couple of days. It's amazing how much noise baffling the passenger seat does when it is there sitting inches above the floor panel.

Without it, I heard all sorts of crap, tire noises, wind, my Intake sucking air... it was ridiculous. When I put the passenger seat back in those sounds were gone (or back to normal state of it being faintly there).

So point is: Extra dynamat, dynasound, fat mat, liquid latex, Jute whatever the hell it is, put lots of it there under the carpet and you'll baffle a decent amount of road noise.

MrGraphics

Go to any decent carpet shop and you can get it.

Simple math would have gotten you a cost. 6ft x 6ft=36 cubic feet. Divide $11 by 36 and you have your cost per cubic foot.

WhiteZed

iTrader: (8)

i bought some felt to do this, but this stuff looks thicker and looks like it will work better, im gonna get some

how you stick it on?? liquid nails or something ??

del105

iTrader: (4)

Probably as heavy too.

MrGraphics

Its not heavy. With the amount of weight i've lost personally, what I've added makes little impact from my normal baseline.

Its not a tangent really - I always thought to myself I should soundproof under the seats. I finally got the gumption up. I personally don't think dynamat is necessary under there though - just the jute. But I do believe that second to the trunk area, under the seat is a major source of noise.

I ran a small strip of spray glue along the top of the jute, then used a couple strips of metal ducting tape to hold the top in place while I put the door on. If you look at the pictures closely, you'll see at the bottom I tuck the jute under the cable bundle to hold it in place.

Once the door is on, it won't move.

dannichols

I got similar results using Dynaliner and neoprene under the carpets. Just another option that is also pretty light.

dmoffitt

iTrader: (4)

imo dynamat is more for curing resonance than blocking sound. you keep a panel from flexing/vibrating with it. felt / jute / whatever helps block certain frequencies (mainlly higher ones)... you need a LOT of mass and airspace to block lower freqs (hence why your neighbor's subwoofer wakes you up at 7:30am saturday). another common misconception is the use of dynamat to cure rattles. use felt to keep the 2 panels from making noise....

not that dynamat isn't great, 2 shop packs in the doors (1 each) of my old honda Element made it sound/feel like a bimmer when you closed it, shut out ALL road/tire noise and really tightened up bass / midbass from the focal 5.25s i had in there.

dannichols

Yes, Dynamat is only great as an acoustic dampener, I only used 50 sq ft. Dynaliner (foam) and open/closed cell acoustic foam do much of the same type of noise cancellation (barrier/absorber) as jute..actually they do it better, but are more expensive.

sharingan625

iTrader: (1)

so when i go to carpet shop, do i ask for "Jute"? is that the official name for it?

thx.

MrGraphics

"On a tip from another board, I went out and bought a 6ft x 6ft piece of jute - or 40 oz fiber carpet underlayment"

sharingan625

iTrader: (1)

thank you~

is this fatmat floor liner pretty much same stuff as this jute stuff?

i heard good things about it.

dannichols

Not the same thing. Fatmat mega floor liner is a foam /vinyl barrier that is thick (3/4") and heavy (1b sqft). foam absorbes sound waves, vinyl blocks it. Similar to other absorber/barriers out there (Dynaliner Extreme) which use vinyl or even lead. It is very expensive, but very good at what it does. Too heavy for the Z though IMO, especially if you are also adding dampener.