Dynamat and Sound deadening

ehidle

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2008 Mazda 3i Touring
So I just drove my Mazda3 to Atlanta and back (and crossed 10,000 miles in the process!) and one thing I noticed is that, at highway speeds, it is LOUD. I couldn't even carry on a conversation on the phone because the noise made it too difficult to hear.

So, I'm thinking about ripping out the interior and applying Dynamat to try to make it quieter.

Has anyone else messed with this stuff and if so, do you know if it will actually help? They have a dozen different products and, since I'm the type to "not mess around," I'll buy the expensive stuff if it's worth it. I'm just looking for some words of experience here. Thanks in advance :)
 
With sufficient money and effort you can get the 3 as quiet as a high-end car, just know that getting it super quiet will involve covering basically every surface of the car with deadener (doors, floor, trunk/cargo, firewall, posts, roof, etc.), and will add weight to the car. I haven't installed any deadener, however in reading through lots of posts on this forum and others the consensus is that dynamat is way overpriced for what you get out of it. A couple of cheaper but good brands I've heard of are b-quiet, and brown bread. Also there are different kinds of deadener, and a combination of different kinds usually nets the best results.
 
dynamat is far too overpriced. You can get similar stuff off ebay for far cheaper. It does help, but you have to be diligent about putting it on the entire car. When I did my last car (95 civic) I noticed the biggest different was doing the doors. Each car varies but I could barely hear any wind noise once I did the doors.
 
google raamatt. as good as dynamat priced like ebay and they ahve great customer service and are a real business.
 
Thanks for all of the advice. Price is not so much an issue - I just want the car to be QUIET. I also don't care about adding 50lbs to the car if that is what it takes.

I really just wanted to be as quiet as my SUV, if possible. I drove my truck to work today and enjoyed the relative quiet. :)
 
I did entire Lexus SC300 with Damplifier from Second Skin (http://www.secondskinaudio.com/). We tore the car apart doing everything from inside the trunk, including the gas tank, to the roof and behind the dash. We even did the wheel wells, inside and out. The car is ridiculously quiet. It is an easy install too, if you know how take everything apart and put it back together at least.
 
before you rip your entire car apart, try changing your tires to quieter ones

That's not the way I want to solve the problem. I want to solve it in a way that is robust enough to handle any tire I happen to put on the car.
 
i gotta tell you man my gf's tires are terribly loud if it was my car i would be pissed (good year triple treads) but my good year eagles are so quiet its fantastic... changing tires maynot be a bad idea gotta realize adding all that wieght to your car is going to take away mpgs...
 
That's not the way I want to solve the problem. I want to solve it in a way that is robust enough to handle any tire I happen to put on the car.

What's not how you want to solve the problem? Intelligently?

No, but seriously, adding dynamat all over won't at all change energy transfer from the wheel, up the strut and into the strut tower. But don't let me tell you how to do what you do(blah)
 
What's not how you want to solve the problem? Intelligently?

No, but seriously, adding dynamat all over won't at all change energy transfer from the wheel, up the strut and into the strut tower. But don't let me tell you how to do what you do(blah)

Your idea has merit, but is nonetheless not a very robust way to solve the problem. Noise in the cabin comes from the energy transferred up the strut resonating in the various components of the car, and the planar components (body panels) are the most effective amplifiers. But, this is not the only source of noise fed to the panels.

There are two ways to turn down the volume of a stereo. You can decrease the input, or you can turn down the volume (output). Turning down the input depends on no other energy getting through the final stage of the amplifier from other sources. Turning down the volume reduces sound from ALL sources.

You're telling me to turn down the input, which does not reduce the noise heard from all sources. I want to turn down the output.

Furthermore, noise generation is not now nor will it ever be, nor should it be, the most important metric for selecting a set of tires.
 
If you are looking for an easier install, I will agree it only does about 80% the job of actual mat, but edead v3 I think it is, is a paint on sound dead. I did the entire interior of my Integra with it except for the headlines and firewall. Road and wind noise was mildly reduced along with exhaust volume. Rattles were completely eliminated. Road noise from rocks hitting the under side of the car adn that sort were also taken down a bit. I use a gallon and a half at about $40 a gallon. On the cheap it can't be beat.
 
If you really want to quiet the car, you're going to have to take off the door panels and take out all of the interior. Pull up the carpet and then go for it. The sound deadening stuff is difficult to work with but in the long run you won't be disappointed. I did this on my WRX and it made a world of difference. I even did inside the trunk. Good luck!
 
I don't mind taking the car apart. Nothing in life is difficult. Things can be time-consuming and require patience, but that doesn't make them difficult :)
 
this is one of my older projects.....man was that car quiet......
 

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wow, thats thorough! even covered the fuel pump access panel :p

seriously tho good job. how much did it total in the end
 
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