cheap sound deadning ??

[HCVP]

Hey guy's, i'm looking for a cheap way to add some sound deadner to my boot, and parcel tray area. Now before i start, Dynamat, is out of the question due to it's price. I know you get what you pay for, but i'm on a tight budget for this install, so i'd like to look at some other options. Has anyone ever used carpet underlay? It comes it in different sizes, thickness ofcourse, and It seems quite dense. I've read an article where it was used to treat the parcel tray area, but they didnt go on to mention if it had any worthwile affects. I figure i can treat the entire boot area for a resonable price, any one have any suggestions or advice..? Oh and can you use anything on the inside of a sub box, or is the MDF best lest to it's own.. This stuff i'm thinking of, or similar, is sold on Ebay $60 for 15m x 1.2 m roll, or that foam style underlay.....??

[bezz]

I used similar kinda stuff under the parcel shelf of my vt, killed all the vibrations so I was happy. You could try it in the boot, dunno how much difference it would make tho.

There's a few different deadeners out there, quite a few cheaper than dynamat too. Whatever you do don't get that crap deadener from bunnings. Also I'm pretty sure Stone and a couple other guys have used RAAmat with good results, you have to import it but apparently works out fair cheaper than dynamat for the same results.

[holdenboy]

Another option which works fairly well is Flashtac, from your local bunnings or hardware store (hope this wasnt the one you are talking about bezz).

It comes in a narrow roll, around 150-200mm wide, so its easy to apply.

[HCVP]

Flashtac huh, i'll check it out. i've seen a few cheapers deadners, but being self adhesive, their still pretty xpensive by the time you do say the whole boot. It's gonna be a long job either way, i post some pics up once i've started and let everyone know what i decide to use and how it goes..

[delcowizzid]

the worst thing with rubber backed carpet underlay is it sweats you should never use it on vehicles under the carpet or in the boot floor under you carpet against the steel floor or you will start rusting pretty quickly

[bezz]

Another option which works fairly well is Flashtac, from your local bunnings or hardware store (hope this wasnt the one you are talking about bezz).

It comes in a narrow roll, around 150-200mm wide, so its easy to apply.

lol i was, from what i hear its thin and doesnt react well to the heat inside a car? Also messy to apply?

[holdenboy]

Ahh its not too bad to apply.....ive used it in my car behind the plastic interior panels and it has given me a small gain in SPL. Not too sure about reaction to heat, havent taken off the panels to look (might now though haha).

Edit: As far as inside the box goes.....MDF all the way

[StoneX]

Flashtac is OK on horizontal surfaces, but vertical surfaces that will get hot can be a problem. People have reported it sliding down their door skin because the adhesive/asphalt can't handle the heat. You would also want to use 2 or 3 layers as it doesn't have much mass to it.

Underlay isn't deadener... It's a sound absorber and if jammed between objects it will stop rattles.

[HCVP]

is that flashtac stuff self adhessive?

[StoneX]

...People have reported it sliding down their door skin because the adhesive/asphalt can't handle the heat...

is that flashtac stuff self adhessive?

Yes, it is.

[HCVP]

So anything that is a sounds absorber, such as underlay, is bad right? i was looking at the actual boot itself, not the enclosue, the bit on hinges.(ok that made no sense at all did it.)
Theres a lot of small gaps in it, should these be filled.. Ive tap tested it and it vibrates pretty bad.. Thanks for the help so far guys.

[bezz]

Its not bad, it just serves a different function to sound deadener (it stops rattles and road noise, whereas dynamat would stop metal resonating at audible frequencies).

I would definitely use something similar to dynamat on the bootlid to stop vibrations. You'd prob only need 1 or two sheets to kill most of it. On my old car i used a few dabs of sillicon in between the actual lid itself and the 'support' i guess you could call it as I didn't want to bother dynamatting- it did the job quite well. For the boot floor in all honesty I wouldn't bother, but if I was to do it I'd prob use dynamat again.

[Timmos]

I bought a box of Stinger "roadkill" for $100

With that i did my boot lid and both front doors (double layer, Over the plastic and on the back wall behind the window).

I'm about to buy another box so i can do the entire boot and parcel tray.

But as for the parts i have done, Very little rattle on the boot lid and GREAT midtones from the front doors. I'm very happy with the results.

[MR_VX]

where do you buy this "road kill" from lad?

[Timmos]

Jb used to stock it.

[Vg-ute-mad]

You are not going to believe it! Do you know those silver windscreen sun shades with the foam backing, that you can get from supercheap etc? Well after taking that crap plastic stuff off, I cut one up perfectly and used it for sealing up the doors using ahesive then sealed up any air leaks with silicon. And funny enough it works well! And I scored some more mid bass. How dodgy and I??? LMAO

[acarmody]

LOL. Thats awesome. Cheapest sound deadener in the world. It reflects light and souns as well. Can imagine going into a car audio installer and saying can you deaden my doors with this please.

[HCVP]

and my boot too !!

[StoneX]

Sealing the door cavity will give you better midbass... It's not acting as a deadener though.

[Vg-ute-mad]

LOL. Thats awesome. Cheapest sound deadener in the world. It reflects light and souns as well. Can imagine going into a car audio installer and saying can you deaden my doors with this please.

and it keeps ya car cool