reducing airspace for subs

[ShawnS]

hi guys

i heard somewhere that you can reduce the airspace in your sub box by stuffing it with insulation. i built my box to the maximum size for the sub, and it sounds bad. i want to tighten up the bass and i figure that reducing the airspace is the best way to do this. any advice?

[shepherd79]

i know that my sub box is stuffed with some white stuff.
i don't think it restrics the space.
what kind box do you have sealed or ported?

[POS carb]

polyfill
it slows down the waves making the box act bigger. Is your box sealed or ported?

[ShawnS]

sealed. so it would effectivly make the space bigger?

[IWLSF]

Yeah, I've heard adding the foam increases the tightness of the hit, but I have yet to see it in an application. It was my uncle that told me to do it, but I guess I should listen since he's been into audio since he was in high school. He said a ghetto way of doing it, without buying PolyFill, is by just go out and finding a nasty, used couch, either on the street, or junk places, whatever. Take the foam from the couch to stuff in there, and leave 6 inches of room all around it. If it doesnt work, it'll be as simple as just removing the foam, so you really have no reason not to try it atleast.

[AccordEpicenter]

yeah you could do that, but youre box is already big, and by adding foam or polyfill its gonna make it wanna act bigger. What the polyfill lets you do is use a smaller than reccomended airspace, because it makes the sub perform as if it was in a bigger box. You need somthing just to take up airspace, like a block of styrofoam or somthing somewhat airtight.