Sound Deadening Doors?
 

Hi guys,

Plan to do sound deadening on the doors only - from my understanding, you do 2 layer on each door right? 1 for the panel and 1 for the removable door card.

Do you think 1 of this Focal Bam XL would be enough for 2 doors?
http://www.focal.com/en/bam-acoustic-insulation/263-bam-xl-3544053822754.html

I got conflicting opinions - some people say not enough some say it's enough.
For those who have done sound deadening on doors only - which mats you use and how was it? Thanks.

It's subjective, the more you do, the more weight you add.

You can add just a little at key points, or you can cover every visible piece of sheet metal and then some. The more you add the more potential you have for a very dead door. At what point you want to stop is up to you. I'd say consider three sections if you want to be really thorough but not obsessed.

The door structure has two skins, outer and inner. Cover the outer as thoroughly as you wish, at least covering the large flat areas. The inner skin will have large openings. Cover as much of this as you wish as well, going a step further you can use pieces of aluminum or perforated sheet metal to act as covers for the openings and cover them with deadener as well to create a more solid "enclosure". Then do the backside of the door card/interior skin, again, as much as you wish.

Adding a second layer isn't completely necessary, but can help. I'd say at least add a second layer in the center of larger flat areas.

and add a closed cell pad or speaker anti-reflection pad right behind the speaker to the outer skin.

Thanks - so from the looks of it - 1 pack of Focal XL is not going to be enough then?

Iirc shop pack if bam is 30sq ft? You can definitely use it for two doors with plenty of coverage. I would just cut it in half that way you add the same amount in both sides.

As far as sound deadening, (especially the butyl rubber/aluminum type) if you think it might not be enough, then definitely get more. You can always use the excess in other areas of the car. It'd suck to have almost enough for what you want to cover, and then have to tear the doors apart again. Do it once and be done.

Also, remember there's different types of sound deadening for different purposes. the butyl/aluminum stuff is only good for resonance/vibrations.

WolfSongX posted a really good guide which I used to do my doors and I couldn't be happier with the results.

http://www.ft86club.com/forums/showthread.php?t=28506

I didn't do full coverage with the butyl/aluminum component and just followed his method of tapping to find the resonances and covering as needed and it turned out great. The closed cell foam acts as a nice super sized gasket between the door card and door. No more rattles when listening to heavy bass music and the stock speakers sound 100% better.

As far as raw materials I went with Second Skin Audio products from the DIY guide above and ordered:

1 x Damplifier Pro (vibration damener) 13 sq. feet - Door Pack
2 x OverKill (closed-cell foam) 9 sq. ft
1 x Speaker Tweaker Kit

I still have one or two tiles of the Damplifier stuff left and some scraps of the foam which I have been using to fix various other rattles and noises.

I also used the WolfSongX method, but on a weight-loss plan. I had some Dynamat Xtreme around from a previous job, so I used one square foot per door, cut into smaller pieces. I used lightweight Polyken flashing tape (butyl/aluminum) to tape all the holes along with the corrugated plastic board from Lowes. No rattles, bass output has doubled/tripled and the door sounds SOLID. Even with that little material/weight, the results were astounding to me.
I couldn't justify all the weight of doing full coverage, but 2 lbs per door was an acceptable compromise.
I should have them back apart this weekend to replace the door speakers, so I'll take some pictures.

Since I am asking local audio installer to do it for me, my options are either:
- dynamat
- focal Bam
- Stinger
Are they all pretty much the same? Or Focal is the best one out of three?

Stinger is what I used. It's generally cheaper and nearly identical materials to Dynamat.

The general consensus is that the outer skin, some bits of the inner skin, and some bits of the door card benefit from deadener. Additionally, the rear quarter panels, trunk lid, and tire well have been popular spots for deadener.

You want to focus on the areas with high vibration energy and high resonant frequency. That's why I advocate covering around the speakers and any place that goes "ting" instead of "thunk" when you knock on it.

I still have some to go... but here's my install: LINK

I've tried many products. Cascade Audio has had best stuff for sure. Check out zero noise website for lots of cool stuff.

http://www.sounddeadenershowdown.com/

This site has some very enlightening information.

Thanks for the info guys. They look pretty full on. Due to budget constraint at this stage I just want something simple done on the 2 doors to mainly prevent the speakers from rattling/buzzing which annoy the hell out of me.

If you do it, do it right.

Most of the stuff you cannot remove plus doing a second layer afterwards mostly have not the effect it should have.

Having said that, looks like buying 1 item of stinger door kit will not be enough to cover the 2 doors then?