http://www.fatmat.com/kits/trunk%20kit.htm

 

Looks good and cheap.

 

Better than Dynamat Extreme ?....

 

http://www.fatmat.com/dynamat/xtreme%20alternative.htm

How dare they use my name to endorse their products!!:rolleyes:

Still Expensive !!!

 

Why can't you just use Carpet Underlay from the local carpet shop to do the floor pan , half the price and i bet it has the same effect

Have you handled that stuff Nelson ?

 

Seriously heavy mate - proabably double to weight of your motor !! :D

Originally posted by konrad

Have you handled that stuff Nelson ?

 

Seriously heavy mate - proabably double to weight of your motor !! :D

 

7 pounds (~ 3 kg) to cover about 15 square feet sounds pretty light to me ! It is being compared to Dynamat Extreme which is designed to be light.

Like I said - just about the weight of your car, doesn't it ?

The whole idea of sound deadening though is that it increases the mass of the vibrating surfaces - this in turn changes the reasonant frequency etc... The whole idea is that it is dense - I don't get how you can get the same effects using less dense materials...

 

CheerZ,

 

Andy

Originally posted by andyduff

The whole idea of sound deadening though is that it increases the mass of the vibrating surfaces - this in turn changes the reasonant frequency etc... The whole idea is that it is dense - I don't get how you can get the same effects using less dense materials...

 

CheerZ,

 

Andy

 

I thought the main idea is to reduce sound travelling from the engine/road/exterior going through the bodywork and into the car. This would not require heavy material. Like putting your hands over your ears to keep noise out.

Hands over ears is different - you are breaking the medium that the sound travels through - air. Sound deadening is to stop panels vibrating - when they vibrate they act just like a sound board/loudspeaker etc. The less vibration, the less sound.

 

CheerZ,

 

Andy

I see - so if the boot was full of rock wool or other stuff put inside speakers, that should reduce the noise from vibrating body panels ? As you know, I'm allergic to mass (why did I buy a 300 ?!:confused: ) so keen to explore ligthweight alternatives ;)

Generally the spray on sound deadening (Noizekiller)is lighter for the same area. I am not totally convinced of this on its own though. Just a fact about some modern sound deadening is that they do not solely rely on mass as the method of damping, they have a very high decay rate (stops panels ringing) due to there elasticity and the way in which they absorb vibration energy and transfer it into heat.

Another thing to note is that it usually a total waste of time, effort and money to lay sound deadening material over the whole cockpit area. It is far more efficient (taking into account weight and cost) to cover 50% of the panel area but in the most likely places for panel resonance to take place (large non reinforced areas) especially around speaker installation positions.

 

Have fun and don't get too sticky.

Or just remove the Ice altogether to get an even better power to weight ratio !

 

V6 24V twin turbo with a Mongoose Exhaust is all the music you'll ever need :D :D

Attaching anything with a thickness and a mass to a thin metal panel (like the noisekiller mentioned above) will change the resonant frequency of the panel to a lower one, which hopefully is less obvious as the human ear's ability to hear low frequencies is fairly poor. Rockwool and many other low density materials will be quite affective against higher frequencies, like tyre roar etc, but I suspect that most of us are trying to reduce the intrusion of mega exhaust noise. I am also investing in spray on 3mm deadening to see if it helps reduce the noise at low revs.

 

I have to agree that at high revs I still like to hear the noise my car makes, and besides, I doubt they've invented anything that could do much about it anyway!

 

I'll let you all know how sucessful my install has been when I get the car back on Saturday!

of course you cannot do anything about the noise entering through the window glass.

Or the Mrs!!!!:D :D :D

As Mr Duff said, these materials are designed to stop your speakers making the panels buzz in an annoying way - not to stop noise from outside entering the car!

 

You would have to block off the windows and roof to have any chance of reducing it.

 

Having said that, they are usually put into cars with very powerful stereos so you wouldn't hear much road noise as it is easily drowned out by the music.

Originally posted by konrad

 

V6 24V twin turbo with a Mongoose Exhaust is all the music you'll ever need :D :D

 

Thats the problem though you see, In Nelsons quest to reduce MASS he has replaced his exhaust pipes with a seris of cleverly connected loo roll centres, only a tenth of the weight but a bugger for noise, hence even the windows now need sound deadening!!!

Originally posted by b19rks

Thats the problem though you see, In Nelsons quest to reduce MASS he has replaced his exhaust pipes with a seris of cleverly connected loo roll centres, only a tenth of the weight but a bugger for noise, hence even the windows now need sound deadening!!!

 

how did u know ?!?:eek: :eek:

Originally posted by ChrisC

As Mr Duff said, these materials are designed to stop your speakers making the panels buzz in an annoying way - not to stop noise from outside entering the car!

 

Whilst this is true Chris, there are lots of things that can pake your panels buzz - vibrations from road , exhausts etc all contribute and the panels will join with anything that contains the right harmonic frequencies.

 

They should also have some token effect as a barrier against sound intrusion, but sound will always enter by the line of least resistance.

 

For the record 3mm (or so) toughened glass will give much better sound reduction than 0.5mm thick steel door panels!