best way to kill road/wind noise

Well, to begin I have a notoriously noisy car (Sebring 2001 Sedan).  I am satisfied with the way my system sounds when idling, but when I start driving the road noise / wind messes everything up.

First, the low frequency noise covers up some of the low frequency noise from my subwoofer.  Basically it sounds like I lose some a few dbs from 40-60hz.  This makes my while-driving bass sound more like a bandpass than a sealed enclosure, as the 60-80hz range then sounds much louder, and I don’t like it.  Secondly, the noise coming through the left door hides some of the sound coming from the left and my imaging is thrown way to the right.

Road noise has never really bothered my before, but now that I have around $1500 sunk into this system I might as well take care of these problems.  I guess I need to start dampening for road noise.  What is the best way to accomplish this?

Will products like Dynamat help w/ road noise?  Dynamat Xtreme any better?   Cascade Audio?

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New Project: 2003 Pathfinder

Did a noobish thing and posted the message w/o doing a search for old posts out of frustration w/ my vehicle.  My fiance's Maxima is so much quieter... anyway, I ran that search and found this:

DYohn] wrote:

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t's called the door seal if it is actually wind coming through into the cabin.  Most so-called "wind noise" is not actually caused by leaking seals and gaskets but by the design of the vehicle.  Wind hitting the side windows off the rear-view mirrors (caused by mirror shape) sounds like it is coming through the door when in fact it is not, and wind coming through the windshield wipers hitting the windshield can sound like your windshield is leaking.  If it is this kind of noise there is very little you can do about it unless you are willing to start modifying the vehicle.

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So, if it is the problem DYohn describes, how can I 'test' this?  I don't want to spend a couple hundred bucks on dampener only to find that the problem can't be fixed.  Any advice?

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New Project: 2003 Pathfinder

A lot  of the noise is caused by the tires, so if you are due for new ones soon, ask for a quiet tread.  The bottom of the car transmits most of the road noise, and you hear it closer to ear level as it transfers through the door panels.  Use spray dampening as an undercoating.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

stevdart wrote:

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Use spray dampening as an undercoating.

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When you say undercoating, do you suggest applying the spray first, then dynamat or a similar product, or are you simply suggesting spraying the floor and/or underside of the car?

Good tip on the tires, I hadn't thought of that.  Thanks stevdart.

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New Project: 2003 Pathfinder

Underside is easiest.  Get enough for the square footage, and it doesn't have to be pretty.  I can't recommend a particular product but have seen some mentioned on this forum.  Then use the Dynamat (or equivalent) where panels resonate from sub freqs, but you will hear those without driving.  And I think you have already done that part.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

If you were to do a search by me as the author you would find this topic asked quite a bit with some good answers.

Here is what I suggested to one guy:

"go wo wal-mart and get a can of bed liner spray. This is a cheeper for of the line-x, Rhino liner stuff and works great. I use this stuff constantly inside every box that I build to both seal the box and stop resonations. Plus it is not that messy or greasy like the undercoating is. You can also spray it up to about a 1/4 inch thick and it wont come off."


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(owner/installer)
Chase's Accessories
Ridgecrest, CA
in business since 92

Thanks for the tips!  Ok .. so for the doors what is the verdict, gang?   Dynamat Xtreme?  A cascade audio product? brown bread?

I'm looking for the best product in terms of damping road noise and ease of application.  I don't mind paying extra for a superior product.

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New Project: 2003 Pathfinder

There was a consensus here recently where Brown Bread won hands down.  But I'm a price-point person, and got a tip here about  polymeric mastic at $14.62 per 12 sq ft sheet, from McMaster-Carr, page 3270 under catagory 'Adhesive-Back Damping Sheets'.  I used it on doors and trunk lid and took out all the resonance rattling.  Compare specs to Dynamat original. 

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Ask your dealer ship about undercoating. I had my Grand Cherokee done for around $150, and the difference was amazing. I used Dynamat before, and like stevdart mentioned, I tried Brown Bread and love it. The adhesive is ten fold better than Dynamat.

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Tim-May!

Why don't you just spray the inside of the door with the spray undercoat or bed liner spray?

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LivnLouder by the paycheck