Couple questions about stuffing sub boxes

[Birdie2000]

1.) What type/brand of stuffing do you use? I've read that the poly-fil you get at Walmart/Joann does very little and isn't nearly as effective as other products such as Acousta-stuf, Black Hole 5, real wool, or even some people say fiberglass. What have you guys found, and where do you buy it from?

2.) My enclosure is downfiring. They say to just pack the stuff in there pretty good, keeping it fairly loose and spread out for maximum effectiveness. Will this cause a problem since it's downfiring and it would essentially be resting on the woofer?

[ibthumpin]

I'm not sure about the various brands/types of fill material - I've only used the polyfill.

I like to put a piece of non metallic window screen on top of the fill material to keep it out of the sub. Generally, you use about 1lb/cuft. Anymore than that and you start losing output according to an article I read years ago.

In aported enclosure I certainly wouldn't use fiberglass insulation, the fibers will break up and travel out of the ports. Fiberglass is very irratating to your nose/throat

[Birdie2000]

Hmm, non-metallic window screen. How do you keep this from moving around in the box, or does it just lay free in there? By "on top of the fill material" do you mean when the enclosure is upside down and you're dropping the driver in? My enclosure is sealed, but even still I know what you mean about the fiberglass. I wouldn't use that. :)

[halfAhoe]

I like to put a piece of non metallic window screen on top of the fill material to keep it out of the sub.
a second vote on the window screen over the fill. Anything phsically getting inside the woofer can potentially damage it. Sawdust, polyfil, etc.In aported enclosure I certainly wouldn't use fiberglass insulation, the fibers will break up and travel out of the ports. Fiberglass is very irratating to your nose/throatAnd depending on how large/powerful the sub is.......dont use any. I was going to use some in my newest box until the woofer was backing out the exterior screws holding it in. I had to put metal/metal screws with more threads to prevent that. I would probably blow all the filler out. Thinking of that stuff killing an expensive driver scurred me.

[halfAhoe]

Hmm, non-metallic window screen. How do you keep this from moving around in the box, or does it just lay free in there? By "on top of the fill material" do you mean when the enclosure is upside down and you're dropping the driver in?A strong adhesive works well. Some people use other things like staples........I just use some adhesive. The filler more or less kills the standing waves, so line the box with it, then you lay the screen over it and fix it in place.

[Birdie2000]

Oh, I always saw people suggesting to stuff the box with it, effectively occupying most of the space in the box (of course following the 1lb per cubic foot rule of thumb), and fluff it up for best effect. I know the MTX Thunderform I had in my Firebird had the thing pretty well stuffed from the factory, and even though some might not think so, for 1 10" woofer in a small enclosure with a POS 180watt amp had a lot of bass. There was just enough room so that it didn't touch the woofer, the rest of the box was full.

[halfAhoe]

Maybe 'line the box' was a bad choice of words. You want to fill the box, but I use spray adhesive to make it stick to the box panels (effectively lining the box). Then if fix the screen over the fill at whatever depth. You have to remember to, just like everything else. Different strokes for different folks. I like covering mine with screen, some just glue it down, some just put screen over the port, etc, etc.

[ibthumpin]

I dont even bother attaching the screen - I cut it big enough so that it cant really move around.

[Dukemaster]

just get the dynomat speaker box kit

[Birdie2000]

Is the black fiberglass screen the stuff you guys used?