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General => Cosmetic and bodywork matters => Topic started by: dubsport on 06 July 2007, 15:33

Title: Sound deadening
Post by: dubsport on 06 July 2007, 15:33
hey,

has anyone done thison there car? is it worth it?

thanks
Title: Re: Sound deadening
Post by: Len on 06 July 2007, 15:39
Depends what you do and where you do it! Also the standard spec of your car!

usual things to do first are the outer door skins or other panels that can resonate. Stick Dynamat on those.
As for floor and roof some good dense underfelt is usually sufficient.

Just depends what youa re trying to achieve?
Title: Re: Sound deadening
Post by: dubsport on 06 July 2007, 15:56
cheers len,

my back box is louder than i thought it would be, and i use the dual carridgeway every day which is annoying because at 70mph all you can hear is the exhaust blearing out.

also the pannels vibrat alot because of the sub ... even when it is on minus so i want to do anything to stop the pannels vibrating ?

thanks
Title: Re: Sound deadening
Post by: Len on 06 July 2007, 16:10
Then some dynamat on the panels that vibrate is what you need to do!

There is a cheaper way - roofing felt and mastic adhesive! But its a very messy job!
Best stick with the Dynamat if you can afford it!
Title: Re: Sound deadening
Post by: Uruk Hai on 06 July 2007, 18:48
You could use something like this :-

http://www.wickes.co.uk/invt/243007?htxt=6YwZAISW1i5OgIudElUVh4%2BI3KMD0YlK3aWM7EPIBJQVvJOxcInvY1H4JwBcSZ2MIfCIMv2VNq1z%0AWJ9bQPNXrg%3D%3D
Title: Re: Sound deadening
Post by: ...joe on 06 July 2007, 19:32
^^^ i used several layers of that on my floor, its good stuff for the money. i did my doors, rear quarters, floor, boot floor and a few other places and replaced all the felt under the carpet. made a load of difference and the dorrs make a nice solid thump when you shut them!
Title: Re: Sound deadening
Post by: dubsport on 11 July 2007, 12:59
ah brilliant cheers guys!

the stuff from Wickes, how many layers would you suggest using?  :smiley:
Title: Re: Sound deadening
Post by: Uruk Hai on 11 July 2007, 19:12
Would be best to start off with one and just take it from there, I only used one layer and that was good enough for me  :smiley:
Title: Re: Sound deadening
Post by: dubsport on 12 July 2007, 00:27
cheers fella ill give it a go in the next few weeks.


thanks  :smiley:
Title: Re: Sound deadening
Post by: Ben Lessani on 22 August 2007, 22:48
I did most of my car, entire floorpan, doors, quarter panels with stuff called Bodyline (knock off dynamat) and to be honest I wouldn't bother again. It only cost me £60 but it didn't really make any massive noticeable difference. Either spend a lot or don't bother is the key, otherwise your just wasting your money.

Read my project thread for pics and comments :D
Title: Re: Sound deadening
Post by: dabill on 23 August 2007, 14:05
the inside of my car is stripped (apart from the dash...)

gonna clean the carpets but also, have had a leak at some point so the felt is prety much fubar now.

whats best to clean the floor surface and would it be good to treat it with anything...

how many roles of that stuff would i probbaly need? guessing about 4ish... also guess it adds alot of weight to the car yeah?

might just do the doors and quarter panels and buy some felt for the floor and cut it to shape.
if i do this, can i get ahold of the felt stuff?

cheers,

rob
Title: Re: Sound deadening
Post by: vr4000d on 30 August 2007, 22:07
second skin is better than dynamat etc the range can be viewed here

http://www.caraudiodirect.co.uk/index.php?manufacturers_id=106&cadid=c77cf16b9c36e4f3211fd5daef104922

Title: Re: Sound deadening
Post by: dubsport on 31 August 2007, 21:16
do you think carpet underlay would drowned out some of the noise? looks the same as the expensive stuff hehe
Title: Re: Sound deadening
Post by: Ben Lessani on 01 September 2007, 18:57
The whole point is mass loading. You want make the panels heavier to that they are less likely to resonate
Title: Re: Sound deadening
Post by: mk2mark on 03 September 2007, 09:40
Just to clarify, resonation frequencies are not bound to an objects mass - the wood I used in my guitar was mahogany, because it resonates at the right frequencies - hasn't much to do with its weight. I think how you apply that to cars is you stick something to the panels to take their resonating frequency out of the range that a car experiences, not to make them heavier. Granted the heavier something is, generally the lower its resonating frequency, but it's not a hard rule, I could have used oak in my guitar which weighs the same as mahogany but resonates at all the wrong frequencies. No idea what my point is, I'm just being pedantic :laugh: Maybe there's a dynamat material out there that weighs the same as polystyrene?
Title: Re: Sound deadening
Post by: Ben Lessani on 03 September 2007, 16:46
Just to clarify, resonation frequencies are not bound to an objects mass... Maybe there's a dynamat material out there that weighs the same as polystyrene?
About right yeah, but the closest thing you can do to stop the panels resonating is to make them less likely to vibrate, adding mass helps indefinately (needs more force to vibrate etc.) Foil backed dynamat has the principal that it reflects sound waves to keep the music in the vehicle. Heres the basics of sound deadening...

Damper – by far the most common type of material. It uses mass loading to lower panel resonance and absorb structural vibrations, converting them into low level heat. Most commonly used throughout a vehicle to control structural related noises. They can also be used in conjunction with a composite to reduce road/engine/exhaust noise. (Extreme &  Ultimate )

Absorber – as the name suggests, these products literally absorb airborne sound waves. The sound waves have to propagate through the absorber and the open/closed cell foam will slow it’s progress reducing the overall level in the process. Most commonly used on floors and firewalls to reduce road/engine/exhaust noise. (Hliner, Vcomp & Lcomp)

Barrier – as the name suggest, these products form a barrier or wall, which blocks airborne noise from passing through. The denser the barrier, the more effective it is, which makes lead an excellent choice for a barrier. Most commonly used on floors and firewalls to reduce road/engine/exhaust noise. (Vcomp & Lcomp)

Composite – Best results are achieved by using more than one of sound deadening, so a composite is quite simply a combination of two of the above types into a single easy to install product. (Vcomp & Lcomp)
Title: Re: Sound deadening
Post by: herbster on 08 September 2007, 13:24
I used matting that gardeners use in greenhouses under the pots for retaining moisture, used a bit of spray glue to hold it in place behind the door cards on the inside panels, quite a few layers under the carpet, makes it fee/look a bit plusher too, one layer under the boot carpet and rear seat.