View Full Version : does polyfill make a noticable difference?

03-25-2004, 05:52 PM
hey, ive wanted to try putting polyfill in my box but does it make a noticable difference, any help wuold be appreciated, thanks


03-25-2004, 06:56 PM
Yep. 1 lb per cubic foot.

03-25-2004, 07:08 PM
sorry, but im confused?? what do you mean by 1 pound per cubic foot? is that how much i need to put in there to make a difference in the sound? and what exactly does it make a difference with, i heard it makes the box sound like its "bigger", is this true? any help would be appreciated thanks


03-25-2004, 08:16 PM
He's not lying to you. 1 pound per cubic foot is what you use, if you're going to use it.

03-25-2004, 08:38 PM
It tricks the driver into thinking there is more available air space than what there actually is. And, yes 1lb per cube is what to use, if your box is 2.5 cubes you use 2.5lbs.

03-26-2004, 08:39 AM
i picked up a 5 lb box of it at wal-mart for $8.00
0r u can pay $2 a lb there

03-26-2004, 10:15 PM
ok lets say u have a 1 cu. ft. box and then u put 1 lb. of polyfill in it.....how big would the sub "think" the box is???

03-27-2004, 09:11 AM
its not really that the sub thinks the box is bigger....it changes the acoustical properties of the enclosure.

when you stuff any box full of fiberous material it slows the backwave. in doing so, you create better low-end frequency response. the amount the backwave is slowed is directly proportional to the amount of stuffing used. If your box sounds like crap below 40hz, pack that sucker full. if it gets a little response but not quite enough, just use the suggested 1lb/cuft.

03-27-2004, 05:06 PM
Is it the same for ported boxes?

and would it change the freq of the port?