greatwhite

I'm looking at adding expanding foam to the vehicles open cavities. The factory already fills most of the voids with the stuff, I'm just going to finish it off..........

Then I'll look at dampening (with a mat product, haven't decided yet but second skin is looking good) the doors first, then the wheel well area's, the trunk and finally the cabin floor area's.

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durwood

CLD or deadener materials are NOT blockers.The aluminum backing has some blocking ability but it would take several layers to do any good. Why do you see people pile it on layer after layer? Because it doesn't do a good job of blocking. You are never going to absorb 50-250Hz frequencies from tire/road noise and exhaust with deadener OR undercoating. All you are doing is changing the resonant frequency of the panel and actually LOWERING it into the same frequency band as the offending noise. This will make it worse.

Absorbing DOES NOT equal Blocking.

Look up "Mass loaded Vinyl", its the next best thing to lead at a 1/4 of the cost. In order for it to be effective, you need to cover the entire floor with it and use aluminum tape to seal it at the edges so that sound does not escape and become airborne.

Take a look at your firewall, it usually covered in this stuff (MLV) for a reason.

Look at it like this:

Noise on the outside trying to get in ->use a blocker
Noise on the inside out of control ->use an absorber
Flat panel materials creating extra unwanted harmonics or frequencies -> use deadener
Panels rattling against each other ->use a closed cell foam gasket to prevent rattling

NRC vs STC

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nobb

Yikes, MLV sure is expensive:

http://cgi.ebay.ca/AudioSeal-Mass-Lo...QQcmdZViewItem

I suppose my car isnt actually THAT noisy...I'm just going to use up my roll of jute and call it a day. I can see how this hobby is going to be a money pit.

I guess plan B would be to save up for a mercedes.

durwood

That roll is 30ft of it, or 135 sqft. What do you drive? A bus? If that's the only place you can buy it, use what you need, sell the rest-but if you can find another source I'm sure you can buy less-I already gave you two names of companies that sell it, now it just depends on if they will ship to Canada.

Seriously, IMO why waste your money on something that doesn't really do much instead of saving up a few more bucks and buying the stuff that does the job right? If the stuff is capable of reducing airborne roadnoise by 10db, how much amp power or acoustic SPL would you need to get that kind of gain above the noisefloor?

Glass blocks low frequenices at about 22dB and the sheet metal in the car blocks at about 12dB IIRC, so all you need to do is lower the noisefloor by 10dB before the glass becomes the limiting factor.

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Megalomaniac

durwood id like to add to your post earlier about the Luxuruy Liner. I suggest if you do use it to be sure to buy that foil tape to seal that liner to the floor. otherwise the sound will "escape" and that barrier wont be as wonderful as you'd imagine.

many steps to deadening. Idea is to put different materials(densitys) to block certain frequencies.

on the floor id probably layer the floor with Damplifier(mat), then go over it with spectrum(liquid deadener), let it cure overnight, then the luxury liner(and tape the edges off with that alloy tape to seal), finally if i cant fit my stock carpet back id recarpet the whole car....I know its extreme but if you really want that "luxury comfort" you got to make sacrifices to do so.


www.secondskinaudio.com <--where i get my deadening

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Defiler

Hair Pile. I used this in my car over sound deadener and it made a world of a difference. Applied it with construction grade liquid nails. Bought a HUGE roll from a carpet remnant place for $50. I have done my entire car, doors and hatch included, including the backs of the panels in my car and I still have enough for a second car.

Road noise went down considerably, doors close and sound like a Lexus.

Good cheap stuff...

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Still have tons of parts for sale!!!

nobb

Ok, so I just did the floor and firewall with about 4 layers of jute. I also took the polyfill from a whole pillow and filled some areas of my dash with it. Wow, what a difference the jute made! This is awesome. It was definitely noticeable and probably the most effective sound proofing thing I've done to my car so far. Maybe not mercedes quiet, but perhaps a toyota camry kind of quiet.

The loudest thing in my car now is the low growl from the engine, and I have no idea how to get rid of that since I already treated the firewall and dash. The engine noise overpowers everything now. There is also a faint grumble from the tires, as well as wind noise at highway speeds. Thats about it.

SuperJ

Cheaper than Dynamat, best customer service I've ever seen, works like a charm:
http://www.raamaudio.com/

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