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Thread: Cotton Batting

  1. #11
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    Well I think I am an idiot because the stuff I am talking about is not cotton batting at all. I am actually not sure what the hell it's called but I can see your point now FoxForce. The stuff I am referring to is grey fiber-like padding/insulation. I picked it up at a local upholstery supply shop. I called them today to see what it is called, who makes it, and what it is made of. The lady said it is polyester strands but didn't know any other details. Sorry for the confusion, here is a photo of the stuff I am referring to:



    The grey foam-like material is the stuff I wanted to discuss. Sorry for my ineptitude :blush:
    Last edited by trevordj; 09-28-2010 at 10:43 PM.
    -Trevor

  2. #12
    gyroscopes and infrared FoxForce's Avatar
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    Looks like jute to me, Trevor. It won't absorb anything besides maybe 10k and above. Put some over your tweeters and test it if you're into practical, unscientific stuff. :thumbsup: It's worthless as a noise barrier.

    When I first got my car, I bought like 100sqft of 1/2" jute (used to be used as carpet underlayment) and put it all over in my car. And I would testify in court that it made my car quieter. But now that I'm older and wiser, I wouldn't do I again if someone paid me to. Why? Because there much more effective and superior ways of tackling those issues. Just because toilet paper and Kleenex look kinda the same doesn't mean they both work the same when it's time to wipe your ass.

    Look, if the stuff does the trick and costs little then that's great. I've MacGyver'd all kinds of sound deadener and other random stuff. All i'm saying is that cotton batting, as far as the sound control industry is concerned, is used as both hot/cold and sound absorption. You can go to Depot and buy a huge bag of shredded denim and spread it all over your attic, in fact. It's a "green" alternative to fiberglass insulation. But like fiberglass, if you stuff it you ruin it's purpose and kill it's R-value. I put a couple hundred linear feet of R-15 fiberglass in the ceiling and walls of my basement for sound control purposes, not really heat. And if I stuffed that in hard, it would severely diminish it's role in the wall/assembly.
    Last edited by FoxForce; 09-28-2010 at 11:45 PM.

  3. #13
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    Oh man, thanks. I feel like a complete retard but that's life I suppose. Thanks for the info for sure. The only thing I wanted the Jute to accomplish was placing a barrier between my amp rack and sub box and the MLV underneath. I have a solid layer of butyl deadener and 1-2 layers MLV throughout the entire car. The surprising thing was I noticed the biggest difference in the noise floor after adding the jute.

    Good to know about the cotton batting still though. What you are saying makes perfect sense.
    -Trevor

  4. #14
    gyroscopes and infrared FoxForce's Avatar
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    Well, I might have spoke too harshly earlier cause I looked at your pictures again and that product is thicker than it looked before. So it guess it's not worthless, but 1 lb/sqft MLV is vastly superior. I'd certainly never recommend anyone recycled textile fibers to block noise.

    In the future, the jute would go under the MLV to create a floating barrier. Unlike damping materials, you want the barrier to move and you want as much mass as you can get in as thin of material as possible. If it wasn't so damn expensive, we'd all have lead-based barriers in our cars cause it has no stiffness and it's damn heavy. We're talking like 15 dB loss at 250 hz in 3/32" tickness (if my old crusty memory serves me :o). Jute would be inaudible in the "road noise" bandwidth. But I suppose it could maybe cut some of the higher feq distraction like wind on the skins, light rain, higher freq tire whistle, etc.
    Last edited by FoxForce; 09-29-2010 at 12:15 AM.

  5. #15
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    Thanks FoxForce, I'm definitely with you on the MLV, it's the ss stuff coupled to closed cell foam to create a floating barrier. The Jute was added as an afterthought hoping to minimize any vibrations between my amp rack/sub boxes and the stiffer MLV. All in all the majority of the hatch (and my floor for that matter) has a layer of butyl deadener, 2 layers MLV coupled to CCF and then then a layer of Jute. My roof also has deadener and CCF/MLV.
    -Trevor

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