Custom Sound Insulation And Damping Materials

[de Noir 0]

Wonder if someone has experience with custom sound insulation and sound damping materials like Dynamat, Teroson, Terodem and like.

Idea is to cut road noise and get quieter cabin + better acoustic from car stereo. And solid "thump" sound when you close the doors. These are all pros.

 

Cons would be adding weight, compromising panel insides for later repairs, compromising rust inspection, compromising drainage paths, etc. I wonder if this is all worth it, in a car like 205.

 

First hand impressions are most welcome...

[MikeHunt79 0]

Wonder if someone has experience with custom sound insulation and sound damping materials like Dynamat, Teroson, Terodem and like.

Idea is to cut road noise and get quieter cabin + better acoustic from car stereo. And solid "thump" sound when you close the doors. These are all pros.

 

Cons would be adding weight, compromising panel insides for later repairs, compromising rust inspection, compromising drainage paths, etc. I wonder if this is all worth it, in a car like 205.

 

First hand impressions are most welcome...

I've never done this myself, but there are alternatives to consider...

 

If it's tyre noise, then you can get lower noise tyres... I think sometimes there can be up to 5db difference just by having a different tread. Unfortunately there isn't much than can be done about wind noise or engine noise...

 

If you do try out some dynamat, I'm not really sure how much difference it would make compared to normal foam. I've found most fabric surfaces absorb sound pretty well, while hard surfaces like metal and concrete tend to reflect sound and can actually make sounds louder! Also, how much weight would it add? I doubt it would would be enough to really worry about would it?

 

Active noise cancellation is kind of cool, but is currently not in production cars yet, only prototypes. All the upsides (virtual interior silence, next to no weight), pretty much no downsides. If you are feeling brave, you could have a stab at doing this, but it may take a lot of tweaking to get it to even work. Expect this to come as standard in new cars in 5 or 10 years time.

Edited February 14, 2008 by MikeHunt79

[All Praise The GTI 3]

back in the 'boy racer days' we used alot of 'brown bread' aka dynamat type stuff. used to stick the stuff in small squares etc everywhere to deaden the vibrations from the BASS!!! its like tar really!!! seemed to work ok

[de Noir 0]

I just want to improve cabin acoustics a little and help car stereo system sound better.

What worries me the most is unability to check what is happening under the damping mats once glued to the panels (it's not that I'm already doing regular check of panel insides for rust! ) and possible metal repairs later..

 

Added weight would be few kilos only, that's not an issue at all. It all comes down to this: How difficult is it to take off when/if needed...

[cybernck 402 1 Cars]

i really don't think you'll need to check for panel rust anytime soon!

[GLPoomobile 958]

What worries me the most is unability to check what is happening under the damping mats once glued to the panels (it's not that I'm already doing regular check of panel insides for rust! ) and possible metal repairs later..

 

I'm concerned by this too. For instance, I wouldn't want to add adhesive material to any of the floor areas since we all know the 205's reputation for letting in water . The last thing I would want is for water to somehow get under the material and sit there, and not be able to see it or treat the area without ripping it all off. At least with the standard carpet and insulation you can remove it easily if you have a leak and easily replace the sodden insulation if needs be.

 

I personally wouldn't have any worries about adding material inside the door skins and rear panels as these don't tend to rust, except around the edges sometimes (such as the bottom of the rear arch where it joins the sill).

[Super Josh 4]

For instance, I wouldn't want to add adhesive material to any of the floor areas since we all know the 205's reputation for letting in water . The last thing I would want is for water to somehow get under the material and sit there, and not be able to see it or treat the area without ripping it all off.

 

Surely by using an an adhesive based material (I assume you mean something like Dynamat and the various other equivalents ?) you would actually be protecting the floor, because with the material properly adhered to the panels all the water could do is sit on or around it and not penetrate through to do any oxidisation damage?

 

 

 

Josh

[GLPoomobile 958]

Surely by using an an adhesive based material (I assume you mean something like Dynamat and the various other equivalents ?) you would actually be protecting the floor, because with the material properly adhered to the panels all the water could do is sit on or around it and not penetrate through to do any oxidisation damage?

Josh

 

I was waiting for that reply

 

In theory, that is sound. But what happens if you are less than perfect in applying it? For instance there are areas where the floor may not be perfectly flat, you may have air bubbles etc. It may be unlikely, but there is the possibility that if not done properly you could leave gaps in the adhesive that could allow moisture to run into and sit.

[de Noir 0]

I was waiting for that reply

 

In theory, that is sound. But what happens if you are less than perfect in applying it? For instance there are areas where the floor may not be perfectly flat, you may have air bubbles etc. It may be unlikely, but there is the possibility that if not done properly you could leave gaps in the adhesive that could allow moisture to run into and sit.

 

 

This is it... Did some research, ICE people aren't too worried about this, at least judging by unbearable easyness of cutting every metal panel that stands between their vision and car structure reality..

 

Dynamat web site klick here if you want to even recommends sealing all holes or leak paths before applying the Dynamat... (see Knocking out the noise PDF)

 

As far as I am concerned, this recommendation is bull***t, as closing leaking paths and dreinage holes means certain death of car like 205! Everything put together, this damping issue upsets me a lot!

Edited February 15, 2008 by MH_

[JamesLumley 4]

There are two sides to using Dynamat...

 

Pros - The rear of my Navara is full of the stuff and it makes the stereo sound 100% better than before it was fitted. It does also cut down some of the road noise but having said that, a Navara ain't the most sophisticated of vehicles to start with!

I installed it with a small wallpaper roller to try and avoid bubbles but it's not the easiest stuff to work with and you do end up with the odd section which might have some air underneath. It's pretty heavy stuff but again that ain't really a problem in a truck!

I would highly recommend to anyone with a decent stereo in a daily car - who enjoys music.

 

Cons - My rally car shell had been completly covered in the stuff when I originally bought it as a road car. When I say covered, I mean every interior pannel had 2 layers including in the wheel arches, doors, firewall, around rear lights - every panel you could access.

The bill just for the matting was around £700!!

It took me the best part of 150hours to remove it and had I known how difficult it would be to get out, I never would have bought the car.

It's like a tar/chewing gum/duck tape (when it's been out in the sun for too long) kind of consistancy and has to be removed half an inch at a time.

It took various chisels, scrapers, electric drills, grinders and god knows what to get the worst of it out and then copious amounts of petrol to remove the remaining tar. Nothing else would touch it - thinners/acetone/turps/white spirit etc.

The silver foil is like working with glass and cuts your hands to ribbons no matter how many pairs of gloves you wear.

Heating it up with a heat gun made it worse and I even tried chilling it without any luck!

 

Dynamat were very helpful in informing me that there was no know product on the market to remove the stuff and hours of searching on forums didn't give me any help other than to keep faith and and keep going.

 

My advise would be think very carefully before using it, if you want to install and forget about it then it's fantastic stuff, if you might have plans to inspect underneath or one day build a track car then forget it!

 

Oh and it's also bloody expensive and you will always need more than you think. To give you some idea my Navara has about 4 rolls in just to do the back (behind and under the rear seats where the sub sits) which is about £250. I thought I bought enough to do the doors but no chance! (unless you cut it into strips which does work but not as effectively)

 

Good luck either way!

[Paintguy 0]

I've been doing a very thorough job on my 205, so I may be able to offer some advice:

 

The kind of products you mention are vibration damping ones, and to be fair, the 205 is pretty well covered (pun intended) as far as the floor is concerned. Some extra may help, but it isn't too bad as it is. You'll benefit from these types of products on areas like the doors, rear quarters, wheel arches and even the roof though. They have very little applied from the factory, and my car is so much quieter after treatment. I've only used the cheap stuff available from bodyshop warehouse, but it does a good job at the price. It's not as flexible as the more expensive products, so is harder to apply, but a little heat goes a long way. If you're staying away from covering the floor, then concerns about hiding rust are a non-issue

 

The vibration damping will stop the panels treated from creating their own noise, but then you need to look at products to absorb road noise. These usually take the form of a dense foam, sometimes with a reflective layer over them). Have a read through the Second Skin for tips, and look out for products like Overkill, or Luxury liner. I'm not sure if you can get them where you are, but Car Audio Direct do the full range in the UK, and may be able to help out. A product like this used under the carpet, around the front and rear arches, and inside the doors and quarters will really make a difference.

 

As mentioned above, it can get really expensive, but you can start off doing the most important areas, and add more as your budget allows.

HTH

Edited February 17, 2008 by Paintguy

[de Noir 0]

Cheers Andy and James... You enlightened the problem well..

 

I thought of doing only doors and rear quarter outer skin, with one layer of the stuff only, not to add too much weight.

I figured about 2,5m2 would be enough for this.

Dynamat isn't that expensive here, I can get Dynamat Extreme pack covering my needs for approx 70€.

There is however very similar material, Soudaband, used in construction, which is even cheaper and apparently does the job equally well.

 

My tactical problem is that having removed door moulding rivets from the door skins and rear quarter bodyshop welded remaining holes and applied body protectant over it. Pre-treatment for applying Dynamat means cleaning everything inside with thinner - which also removes protectant - and highly likely this could end exposing unprotected welds to water and condensate.

 

In case I don't get Dynamat applied absolutely perfect, there is high chance of drainage water and condensate staying between metal and Dynamat... What happens next is not hard to imagine. Due to configuration of the door and nature of Dynamat itself, man would need to apply it in patches, leaving lot of room for uncontrolled condensate and water wonder inside, far from sight.

 

Doing metalwork on my shell I found ugly rust and holes in metal, caused by water finding its way under panel sealer and staying there, would not like to have this sort of problem again on sorted shell... Too many hours already spent to ruin her this way.

 

So I decided not to do it.. Thanks for your suggestions and comments.

Edited February 18, 2008 by MH_