I'm in the ordering/designing stage of building my subwoofer box when a thought/question came across me.

Is using polyfill AND sound deadening (i.e.-v1) more beneficial than using just one or the other?

I have not seen anyone state they used both. Redundant use of materials? Bad for sound wavelength reason? ...or am I just missing it?

 

What do you plan on using the polyfill for? Usually polyfill is used inside the sub box to make the sub "think" its in a bigger box.

 

For clarification...this is for the inside of the box for dampening purposes.

 

There's no need to put damping materials (such as dynamat, etc.) in a sub enclosure, unless the material the box is made of has resonance problems.

 

For some reason...I trust your opinion more than the sites I am reading.

They say it may help in killing bad resonace. This was the best and most technical explanation I could find after 11 or so Google pages of search at 200 post per page.

I thought it might be hog wash. I have built multiple boxes (even crappy ones that I learned on) and none of them bothered me sound wise.

What else fueled this is someone stating they eDeaded their box....well they meant their xB! That's what I get for reading it at 2 am..

 

Plenty of HT enclosures will go to extreme measures to eliminate the resonance of an enclosure-- including using steel and concrete. In a car, the sub box is just an enclosure inside an enclosure (the car), and the best you can hope to do in a car is lower it's resonant freqency-- there are parts of it (like glass, the engine, and other moving parts) that you have no control over.

Build the box stiff, use an acoustically dead material like MDF, and you'll be happy with the results.

 

I'll just buy the $3.99? or so polyfill and be happy!

 

fiberfill works wonders.

I have a 12" kicker comp in a 2cubic foot box and its fiberfilled w/ $1.49 of walmarts' best!!!

before that, i have the kicker comp installed in a .75 cubic foot box... (wayyy to small) and it sounded excellent AFTER it was fiberfilled.


for the price...just dew it

 

Actually...I found out where I got this idea to begin with.

I just received my new subs. Well, prior to buying them I got all the info I could and compared the different models I was interested in.

Anyways...in the manual it states in two seperate locations "Line the interiors of the subwoofer box with sound absorbing material..."

Now I know sound DEADING and sound ABSORBING could be the same or different.

I have also noticed a lot of home stereo loudspeakers are also made with a sound absorbing panel on all sides of the box except the plane the sub is on.

I have noticed both sides of the coin..some say "It's crap!" ..most say it is highly recommended.

It also appears the consensus is that the top product for sound purposes (from best to worst) is long hair (strand) wool, Acousta-Stuf, foam dampeners (egg crate or flat studio panels), and then Dacron or polyfill.

Can't seem to find wool batting or wool at all at the local fabric and craft stores. Plenty of the cheap polyfill. No sound deadening foam unless they have it at Lowes or Menards. Acousta-Stuf I have only seen online. The few stereo shops here don't have much of a selection.

So..I'm still trying to figure what to do..