Instead of forking out hundreds for cheap rubber sheets, I've stumbled upon a material to use as a replacement that should (in theory) work better.

The answer is in carpet tiles. They are square tiles of rubber with carpet on one side that are glued to the floor, mainlly in offices and the like. When they need new carpet, the old stuff gets thrown out. Sure, people have been walking on it, and it may smell a bit funny, but noone's going to see it on the inside of your panels.

Is there any reason you guys can think of that would make this stuff not as good as dynamat or g-spot or stinger sound deadening material? Surely a carpet surface would absorb more sound and reflect less than a flat rubber surface! And surely the carpet rubber would have a simmilar effect on the harmonic and resonant frequencies of the door!

What do you recon?
This stuff is free, come on...

Even though it's only 1:30am in the morning, that still is by far the funniest thing I'll read today..

Whether it'll work just as good? I don't know, I doubt it infact. You have it under your carpet in your home yet it vibrates when you have your home theatre subwoofer going, does it not? Eh, give it a try, I wouldn't mind seeing the results.

The aim of sound deadening is to decrease the resonant frequency of a panel. It does this by adding weight, usually in the form of bitumen based sheets, or sound deadening paint.

So in short no, this wont stop ur problem. Spend right, do it right the first time. Otherwise you'll make a big mess. I've tried and researched heaps of cheap options for sound deadening and your best bet is to go with Dynamat or Stinger expert.

I wouldnt even recommend using Jaycar Sound deadener as its too thin.

There are a few things you need to overcome in car audio, you have:
Reflected waves: Bouncing off the back of your door or sub box back onto the cone of the driver causing distortion. -> This can be stopped using acoustic tiles behind ur driver.

Resonace -> Which is the actual resonance of a panel as a wave equal to its resonant frequency comes in contact with it (eveything has a resonant frequency, it can cause standing waves to occur in bridges if the wind is strong enough) Generally u can tell if you have this as when u sit on the panel it will stop resonating. It usually occurs on large thin areas such as doors and boots

Rattles -> Caused by two objects vibrating against each other, solved using any object, cardboard, foam etc, to separate the two objects

Road/ambient noise -> Caused by the noises on the outside getting in. Tyre noise, engine noise, traffic, etc. Sound deadening will reduce this to some extent, but sound proofing will help most. Eg insulating layers under carpet etc.

Induced noise -> Alternator whine, ground loop etc... off topic for now...

Ur carpet MAY, reduce rattles, and ambient noise. but wont stop the actual problem of resonance.

Peace

Tim

double up on that.

Sound deadening is not plastic sheets, have you ever seen the stuff before?
Its like *****ium/tar, very heavy/dense.

The stuff you are talking about will do absolutely jack ****. Well might make a minor difference but prob not even noticable while driving.

If you are worried about the price, go buy a pack of bostik sound deadening, 24 sheets enough to do doors boot bla bla bla and can be had for like 60 bucks.

Works treat, how do i know? cuz my boot use to flex a few cms and sound like a tin shed in a hail storm, i used the bostik stuff and now my boot is hard as a brick wall and doesnt budge.

s_tim_ulate, what do your recommend for doors? Dynamat or Stinger?

I've used stinger roadkill on the boot lid, but I wanna get some done on the doors


Edit: Also..what's the difference between these two:

Stinger Roadkill RKC12
and
Stinger Roadkill Door Kit

It's the same amount, except the former is like $50 cheaper...

(added a bit more to my last post too...)

I used Stinger roadkill on my doors and sound off paint.

I would go with the Dynamat if I had another chance though. Stinger is easier to apply though, and they are both very good quality in comparison to other brands.

For the back of your trims use Sound off paint, works a treat and sets like concrete.

i used a door kit + a bit more to do my doors, i needed a lot as i filled up the service holes with mdf, so needed to cover them too.

Im not sure otherwise if it's cheaper for the same amount then go for it. Double check the quantity though.

Peace

Tim

nice, I'll have to check the bostik stuff out.

I have seen the stuff, which is why i recon gluing a panel of rubber carpet tile would do the trick. It's heavy rubber, much like the dynamat i recon, just thicker. Maybe 5mm thick rubber sheets. I figured if I glued them to the inside of both door skins, it would work the same way? Adding an even layer of dense material to the entire skin to stop or reduce resonance?

I think the RC12 pack is just not as good as the "Expert" series, same amount, but if it's $50 cheaper than the material used can't be as good..

But it's not actually part of the panel. Its just stuck on. The bitumen compound becomes one with the panel as it is sometimes made up of 95% bitumen and only a thin foil backing. It is the bitumen that absorbs the resonance. Not the foil.

The only thing that will be absorbing the resonance here is the thin layer of glue you use to stick ur carpet on with.

The carpet may help out against reflections and will probs reduce road noise, but for the added weight and mess that will follow, I don't think u should waste ur time.

If there was a quicker/cheaper way someone else would have found it by now.

Peace

Tim

I think the RC12 pack is just not as good as the "Expert" series, same amount, but if it's $50 cheaper than the material used can't be as good..
Ah soz, missed that, the expert series is meant to be the only decent stuff they have, much more dense compared to others.

I would only use this and Dynamat, If you can get dynamat cheaper than stinger expert roadkill go for it...

Sorry to slightly change the subject, but I just looked at Dynamat's website (dynamat.com) and these people are kidding. They've got like 10 products just for sound-deadening, what the hell? A product just for the speaker? It's like 2sq ft...ugh..Even though sound-deadening is great, you really can't justify the pricing.. :(

Ah soz, missed that, the expert series is meant to be the only decent stuff they have, much more dense compared to others.

I would only use this and Dynamat, If you can get dynamat cheaper than stinger expert roadkill go for it...


Yeah, I can get Dynamat Door Kit for $140, Stinger Expert Roadkill Doorkit at $150..hmm, should be interesting (except I gotta get the dynamat stuff from Alberts from WA, $130+$10 postage)

yeh it loses its effect the more money u spend on it.
Aim for $150...

I think i've put in a few hundred into mine... Boot, parcel shelf, backseat, doors (inner, outer, trim)

You can never stop the rattles though, u will eventually rattle ur car apart.

Heh yeah, it's all fun and games though, keeps a man occupied :|

I need some sound deadening for my boot and then i'll be right, whats some cheap stuff i can get? dont really wanna pay over $50.

I have a spare pack of jaycar stuff... You can have that for $20...

Should be enough to do most of the boot. But as I said b4 it's not as good as other brands. I'll bring it on Sunday

i still have 2 complete door kits left over from my sound deadening experience ... it's dynamat and i was supposed to do the parcl shelf with it but i sorta lost all interest in it

i still have 2 complete door kits left over from my sound deadening experience ... it's dynamat and i was supposed to do the parcl shelf with it but i sorta lost all interest in it

oh no, u've lost interest in car audio or just sound deadening ur parcel shelf?

oh...yeh, carpet rubber stuff ain't gonna do shiit for u lol. though, u could try carpet as a wavebreaker thing behind ur speaker...but its still a bad idea as it'll probably suck up water when it rains.

Ive seen people use carpet underlay as a soud deadener in there boots, would that really work

Nope, this is sound proofing... It will (to some extent) stop the transmission and reflection of sounds through the boot itself, but won't do much to stop resonance.

so the spray on sound deadener is a good way to go, i tried using some stick on stuff from Wurth its about 2mm thick , but as megatron can testify it did bugger all. I am going to double it up, but would like to have it work as best as possible so i was considering spraying the other stuff over the top. Would that work??

Yep is easy to go over the sound deadening sheets with the spray on stuff...
Will make it very solid

what's the spray on sound deadener called and worth ? might look at doing my car with that as well

though i'm still waiting for the cans of Anti-Rattle for my boot to come into stores ... apparently everywhere i go say they are on backorder

I use sound off. A 1 litre tub costs $65-$70, can be watered down and sprayed on, or just painted on.

Can be bought from specialist car audio shops.

Otherwise u can buy k&n sound deadenening paint, but this is not as good.

not sure what the stuff im gettin is called, the place i got the stick-on stuff from are giving it to me cause i complained about it. I think its a wurth product so who knows

throughout my car dynamat has been used! does wonders!! but taking a closer look at it i found it was exactly the same as roof tape or gutter tape from bunnings! same thickness and same foil backing! ended up puting it in a mates sigma with amazing results! a $45 roll done all 4 doors and boot!

Flashtac is what ur talking about, and its not the same thickness as proper sound deadening. I know many ppl who have used that and it doesnt end up being cost effective. You need 3 layers to get the same effect.

Also don't put sh!t like expandafoam in ur boot. will wreck ur body in no time.

There are no cheap alternatives. I spent 6 months looking for cheaper ways to go about it. 5 or 6 products later and i settled with the stinger expert. I would only use this, dynamat, or astromat now.

I dont know whats in my boot. I think its just plain sheet rubber (about 3-4mm thick) glued to underside of the lid. Works well, even though the summer heat has made it go hard. The boot lid is the only part of the exterior of my car that doesnt rattle.... Just gotta sort out my bumper, roof, exhaust, number plate, etc... Dunno how much it costs but cant be more expensive than dynamat.

not sure what the stuff im gettin is called, the place i got the stick-on stuff from are giving it to me cause i complained about it. I think its a wurth product so who knows
hey, just get that pack of stinger roadkill kit off alan. i was supposed to get it, but unexpected expenses and i had no job back then. about $115 i think it was

hey, just get that pack of stinger roadkill kit off alan. i was supposed to get it, but unexpected expenses and i had no job back then. about $115 i think it was


Why pay when i can get it free :nuts: lol

The reason why Stinger and Dynamat cost so much is for 3 reasons:

a) Their product is vastly superior in sound dampening when you look at temperature ranges; all the cheaper stuff is sometimes similar in performance, but the effectiveness drops off rapidly when you drop out of the common temperature range of ~20degC.

b) Huge marketing budgets; they both sponsor all the major team + individual competition cars, so the money has to come from somewhere, you.

c) Because they can, and they know they have a good product and people who want the best will always pay the most.

In saying that, I have used a product that used to be distributed by CarAudioAustralia, Gspot Extreme (the thicker of the 2) adhesive + foil backed sheeting, and also Gspot liquid paint-on deadener. I covered all surfaces (Inner and outer door skin + inner of door trim) for around $150. Bootlid is fine with the stock carpet trim as I'm only running around 200WRMS through the sub.

Don't bother with the cheap cheap stuff, as like already said, it does a crap job and will leave you with a molten sticky mess later.

Sucks that CAA have closed up their shop, they used to be a goldmine...

I just ordered 4 sheets of Stinger Expert Roadkill from JB HIFI. $130 :D
They dont stock it, but can order it in.
Hopefully I'll get it all in on Sat!!

:cool:

The reason they don't stock it is because of the pricing, they can't really go much lower than the RRP of it.

The RRP is $179 so thats a reasonable drop.

RRP is $160, costs a trashload to bring into Australia

I just ordered 4 sheets of Stinger Expert Roadkill from JB HIFI. $130 :D
They dont stock it, but can order it in.
Hopefully I'll get it all in on Sat!!

:cool:

just outta curiousity mate - how far will those 4 sheets go?? - do you intend on just putting it on your outer door skin, or both inner and outer?

ricbec... pm Marty aka FHRX... He is selling BULK PACKS of DYNAMAT for $230... Thats ridiculously cheap!

I dont know how long it'll last for so do eet now!

There's 36sq feet per pack

Half a bulk pack is more than enough to do your front doors. A bulk pack is enough to do the doors and boot with leftovers for the parcel shelf etc...

To put it in perspective 12 sq feet of stinger expert (their 2 door packs) is equal to 4 sheets at $130 (rrp $160) (as above). Since its the same stuff, if my maths serves me correctly at that rate you'll save $160 buying a bulk pack off FHRX even off the already cheap jb hifi prices

Peace

Tim