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Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag

Brand:|Part # 260-317
Acousta-Stuf, a synthetic material made from crimped fibers, is an excellent choice for filling or stuffing small enclosures or transmission line cabinets.
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Part # 260-317
  • Higher performance than natural fibers, easier to use than fiberglass
  • Improves bass, tightens midrange, increases dynamics
  • Super-stable, won't decompose, doesn't attract insects
  • No mask or gloves required!

Product Details

Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag

Acousta-Stuf, a synthetic material made from crimped fibers, is an excellent choice for filling or stuffing small enclosures or transmission line cabinets. Long fiber wool has been a favorite among serious speaker builders but Acousta-stuf is less expensive than long fiber wool and does not have the problem of harboring moths. Acousta-Stuf™ also outperforms Dacron, foam, and fiberglass.

Acousta-Stuf sound absorption damping fiber deepens bass, provides cleaner midrange, and improves the dynamic extension of any speaker system. There are no health hazards with Acousta-Stuf and no mask or gloves are needed when using this product; the melting point is a very high 490°F. Most sealed and vented enclosures require 1/2 lb. of damping material per cubic foot of enclosure. For best results it is recommended to loosely fill the material throughout the enclosure.

Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag
  • BrandParts Express
  • Part Number260-317
  • UPC844632037382
  • Product CategoryCabinet Damping Material
  • Unit of MeasureEA
  • Product Rating
    (67 Reviews)
  • Weight1 lbs.
  • California Prop 65

    Warning: California residents only. Please note per Proposition 65 that this product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.


Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag
Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag is rated 4.4627 out of 5 by 67.
Rated 5 out of 5 by from Acoustic Polyfill Sound Damping.This Acoustic Polyfill was used in a 2cu Ft Parts Express Subwoofer box, this stuff is hard to beat, One of the best damping product you can buy,
Date published: 2015-10-19
Rated 4 out of 5 by from Good Poly-Fill Matting for cabinets.Good Poly-Fill Matting for cabinets. I prefer the "speaker pad matting better but was unable to source it. This is good poly fill but too expensive and hard to glue down.
Date published: 2015-05-14
Rated 5 out of 5 by from Works as designed - deeper bassRebuilding several old speakers and upgrading in the process. This fill was part of the upgrade.
Date published: 2015-03-15
Rated 5 out of 5 by from Great itemI got this material for my two sub boxes measuring 2.7 cu.ft. each. The speakers installed were ment for a 2.1 cu.ft. box. The sound coming from them was weak and the bass wasn't that deep despite the 1500 rms @ 2ohms they were getting. After accousta stuff was inserted into the boxes, their bass came alive. The sound is a lot better my house walls vibrate enough and I'm a happy customer, thanks.
Date published: 0001-01-17
Rated 4 out of 5 by from Nice productI am pleased with this product, the only thing is that I have to buy like 4 more pounds for my application.
Date published: 2014-10-06
Rated 5 out of 5 by from Fantastic ProductI purchased PE Acousta-Stuf Polyfil, #260-317, 1 lb., to tame the bass in the Dayton 652 PE speakers. I added 2 oz. recommended by reviewers. Incredible. It tamed the boom of the base to a cleaner tone. I have a bout 12 oz. remaining, that will be used in the speaker cabs I am prepping to build. I have used quilt or pillow batting before, however, the Acousta Stuf is the real deal. It is a little more dense than batting and really dampens cabinet resonance very well. Thanks PE. Your products keep me coming back.
Date published: 2014-10-05
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Product Q&A

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Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag

Can you use this in your wall with wall speakers to reduce noise transimitting through the walls?  Or is there something else recommended.  I have speakers between my living room and bed room and would like to reduce the noise.

Asked by: smdoyle63841
This is not rated for in wall use, but you can use standard fiberglass insulation to help with this.
Answered by: MattP
Date published: 2016-01-21

I am trying to design a transmission line enclosure. How much is the speed of sound slowed by this filling.  Does the percentage change with frequencies.

Asked by: mark47803
The speed of sound is not slowed, rather the stuffing absorbs the back wave. This is frequency dependent, and the longer the wave (lower the frequency) the more material is required. Generally TL's are stuffed from the rear of the driver to the terminus, the amount or density of this stuffing is determined by the end user.
Answered by: MattP
Date published: 2015-06-29

If I have a sealed cabinet that is .53ft^3 how much of this should I use?

Asked by: thatnoob
We recommend starting with a half pound per cubic foot of volume, this means you should start with about 1/4 of the bag. You can then add or remove stuffing to get the sound you want.
Answered by: MattP
Date published: 2014-03-17

Hello How much Acousta stuff polyfill material do i need to fill two chambers of 2,5 cf volume each?

Asked by: Jonvold
There is no right or wrong answer for this. We usually recommend about a half pound per cubic foot of airspace but you can adjust to suit to personal taste.
Answered by: MattP
Date published: 0001-03-02

what kind of cabinet is this for?

I'm building a pair of ported bookshelf speakers, is this suitable for dampening them (each cabinet is roughtly 2 ft^3)? how does this compare to regular acoustic foam?Thanks
Asked by: ben199
I generally recommend stuffing a sealed cabinet and lining a ported cabinet. Both products work to achieve the same result but in two different ways. I usually use standard fiberglass insulation or Sonic Barrier sheets for ported cabs.
Answered by: MattP
Date published: 2015-06-29

When using Polyfill, is the volume of material or the weight (density) of the

material more important? If you use 1lb per cuft and the fill settles, do you need additional fill? Which dampens more - the volume or the mass.
Asked by: WaxLips
It doesn't settle. Most of the time it is sticking out of the box and you have to mush it in to fit the driver. I weigh it out on a digital scale in a plastic salad bowl. I take little clumps and pull and pull to get a uniform density. The pile ends up being huge and if you mush it then it will pop right back. I suppose you could say the weight is a suggestion. One pound will give you a certain volume no matter how much you fluff it out. My old boss used to stuff it in pantyhose, tie off the leg, and throw it in. Personally, I like to stretch it for all it's worth and lay out many thin uniform layers to cover all internal spots of the box.
Answered by: musiCal
Date published: 2013-07-06
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