i saw a couple of sub boxs at this local audio shop and they had what looked like cotton ? in them...anybody know wat the hell im talking bout? looked like it was used to take u space inside...if im not crazy then whats the point in this?

 

It's called poly-fill. You would think it would take up space, and it does, but it actually makes the sub act as though it were in a bigger box. It's normally used in boxes that are small to make the sub play lower. It works by keeping acoustics from echoing inside the enclosure, blah blah blah... it just works But too much decreases subwoofer output.

 

i might try this then..i have 1 cu ft of air space in a single 12 " box that will go under my rear passenger seat. you mentioned to much is bad...how much you think i should stuff in? the sub is an alpine swe 1242 if that matters

 

That sub says it can be in a sealed box volume: 0.8-1.7 cu. ft.

Your supposed to put roughyl 1 lbs per cubic foot......I would put a little under 1 lbs and see how you like it...you should really mess around with the amount inside and find how you like it....

 

What he said

 

Quoted for truth.

Something I will suggest that you do is before you deal with the polyfill, consider improving the inside of the box by making sure all the corners/edges are completely sound proofed. This will also help improve sound quality and helps to keep your sub in good working order. I

 

you mean re calking the insdie right? what else aside form calk cna be done? oh and is it just normal silicon sealant?

 

You can also reinforce the actual box by putting traingle braces in the corners. Every bit the box flexes its converting sound energy into mechanical energy which can reduce output. It wouldn't be at all significant on a small box, but it's a good general rule.

 

Polyfill dissipates energy in the form of heat from vibrating, which the sub feels as more damping. And to get more damping, you would need a bigger box. So basically it's a small cheat which works well. I've got two Infinity Perfects in my Camaro, and can tell a difference with and without it. Sounds much cleaner, which is good considering Perfects are clean as is. Just don't go overboard on the stuff, more is not better. Just line the walls and make a nice bed with it.

 

and keep it light and fluffy , don't pack it down