free shipping at parts express

Acousta-Stuf Polyfill Speaker Cabinet Damping Material 5 lb. Bag

Brand:|Part # 260-330
Acousta-Stuf, a synthetic material made from crimped fibers, is an excellent choice for filling or stuffing small enclosures or transmission line cabinets.
In Stock
List Price$65.99
You Save29%
Your Price
Buy 5-24 $39.38
Buy 25+$36.67
Part # 260-330
  • 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 Damping Material 5 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 Damping Material 5 lb. Bag
  • BrandParts Express
  • Part Number260-330
  • UPC844632037399
  • Product CategoryCabinet Damping Material
  • Unit of MeasureEA
  • Product Rating
    (28 Reviews)
  • Weight5 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 Damping Material 5 lb. Bag
Acousta-Stuf Polyfill Speaker Cabinet Damping Material 5 lb. Bag is rated 4.5714 out of 5 by 28.
Rated 5 out of 5 by from Good StuffUsed to replace some burnt original filler. So far so good, can't notice any difference from other more fortunate original speakers.Easy to work with and does not make too much of a mess when using.Happy with results.
Date published: 2015-01-14
Rated 4 out of 5 by from product worksI used Acousta Stuff in a set of Klipsch Heresy Is. After treating the speakers, they are much less boomy, and the response is flatter. I would recommend not over stuffing - stick to the recommended amount which is more than enough. Also, it;s not necessary to spray glue the poly material in place for a sealed cabinet.
Date published: 2014-07-08
Rated 5 out of 5 by from a little goes a long way to ear happinesshad an older pair of PA speakers (600 Watters) that I thought I blew the super tweeter. Opened up the unit to find a cold solder joint that was easy to repair, but since I ripped into this plastic housing, noticed it was a low cost construction and ordered four pounds of Acousta-Stuf to deaden the back-waves as well as glue up some of the larger components on the cross-over (a little labor of love goes a long way). WOW ! that speaker sounded so much better, that 15 inch mid-woofer was so much better sounding that I ordered another 4 pounds of Acousta-Stuf to fill up the other working unit, of course I also hot glued those larger caps on the cross-over as well. Now that music room sounds so much better during jam sessions.
Date published: 2014-05-07
Rated 5 out of 5 by from Damping DeliciousHandles well, easy to work with. Light yet heavy. Dense yet fluffy. Acoustically sublime. Goes especially well with a 2008 Domaine Louis Michel Chablis Fourchaume Vaulorent.
Date published: 2013-08-07
Rated 5 out of 5 by from Great productThis is great damping material. I had a set of speakers that were filled with fiberglass dampening from the factory. I replaced the fiberglass with Acusta Stuf and increased the bass output. This stuff works. I have stuffed all my speakers with this dampening material and they all now produce deeper bass. It is a bit expensive but the results are worth it.
Date published: 2013-04-21
Rated 5 out of 5 by from Buy It!This product just plain works as advertised. As a added bonus, it is easy to cut/tear & does not itch like crazy if gloves are not used.
Date published: 2010-01-09
  • 2016-02-12T06:29CST
  • bvseo_cps, prod_bvrr, vn_cps_3.1.6
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_28
  • loc_en_US, sid_260-330, PRD, sort_mostRecent
  • clientName_PartsExpressInternational

Product Q&A

Get your questions answered from other customers
who own this product or have experience with it.
If your question requires design or troubleshooting information,
please email  for a prompt reply.
Acousta-Stuf Polyfill Speaker Cabinet Damping Material 5 lb. Bag

I am building a 3 cubic foot subwoofer cabinet (with Dayton Audio SPA1000 1000W Subwoofer Plate Amplifier and Dayton Audio UM15-22 15" Ultimax DVC Subwoofer)and would like to know if two 1lb bags of poly-fill would work ok instead of 1-1/2 lbs?

Asked by: markhea1
Yes 2 pounds will work just fine for this subwoofer. You can always remove some if you would like, but I doubt you will notice any difference in the sound.
Answered by: MattP
Date published: 2015-07-22

is this ok for down firing subs?

Asked by: mike y
Yes this will be fine for a down firing application.
Answered by: MattP
Date published: 2015-03-11

Would you recommend this product or egg crate for a transmission line subwoofer?

Asked by: Bigkan
I would recommend Acousta Stuf for a transmission line type enclosure.
Answered by: MattP
Date published: 2015-01-12

What is the volume of bag?

Asked by: sosokruashvili
A 5lb bag of polyfill can accommodate up to a 10 cubic foot enclosure. Recommended use is 1/2 lb. per 1 cu ft.
Answered by: TomI
Date published: 2014-10-09

Would using acoustic foam be better if it has a better absorption capabilities than Polyfill?  Is there any RAL measurements on Polyfill that I can compare to acoustic foams on the market to compare effectiveness?

Asked by: BobSm
Acoustic foam is excellent for damping the walls of a vented enclosure, whereas Acousta Stuf or polyfill is used in sealed enclosures for changing box Q and absorbing midrange back wave.
Answered by: MattP
Date published: 2014-03-07

Making enclosures seem larger formula

Is there a formula for how much Polyfil results in an effective increase in enclosure size? I have a sub that wants 1 cubic foot. Can I make it work in an enclosure of .7 using enough polyfil?
Asked by: dB Cooper
I'm certain that you could calculate that if you had info on all of the known variables. The problem is that you would have to know exactly where each strand of polyfill is in the cabinet to know how it would physically interact with the sound waves being sent into the enclosure by the driver.The layman's way is to simply add 10% to the enclosure size for a sealed enclosure loosely stuffed with polyfill. Also note that you can overstuff for negative effects, and I personally don't like to use polyfill for ported designs. For those I like to line the walls with egg crate foam or better quality foams (I have heard carpet padding works as well).So aside from a very complicated calculation that would require computer assistance, just add 10% to your enclosure size and don't overstuff.
Answered by: Honest Rob
Date published: 2012-05-30
  • 2016-02-12T07:08CST
  • bvseo_cps, prod_bvqa, vn_cps_3.1.6
  • cp_1, bvpage1
  • co_hasquestionsanswers, tq_8
  • loc_en_US, sid_260-330, PRD, sort_recentQuestionsFirst
  • clientName_PartsExpressInternational
Parts Express FacebookParts Express TwitterParts Express YouTubeParts Express PinterestParts Express SpotifyParts Express Instagram
Live Chat Software