Stuffing

[Dave Jones]

I've got a pair of JX92S speakers (T/S parameters below) and a couple of boxes with an interior volume of about .3 ft^3. I'm going to use the boxes sealed, and employ a subwoofer. A friend who owns a high tech machine shop is cutting the holes in the front baffles for me. I may be the only kid on the block with counter-sunk speaker cutouts accurate to 0.0005 inches! While the baffles are in the shop, I have until Monday to fret over how I am going to stuff the boxes.

The boxes are the prefinished ones from Parts Express. They are absolutely gorgeous, and very solid. Not exactly DIY, so sue me.

I would prefer not to use much if any glue to stick damping material to the inside of the box. I did that with the last set of speakers I built, and I made a big mess. On hand, I've got some open bubble foam from Parts Express, and also a bag o' poly fiber from the local crafts shop. Are those materials sort of interchangeable? Does the foam make the box effectively larger (like fiber) or smaller, or what? One can pretty much fill the box with fiber. Is the same true of the foam?

How would you stuff those babies?

T/S

Qts 0.4
Vas 15.28 Liter
Fs 45 Hz

[Dave Jones]

The short version:

What are the practical differences between fiber fill and "egg crate" acoustic foam?

[knorke]

Since you have foam and fiber stuffing I would put a piece of foam on the backwall
and fill the rest of the cabinet with fiber stuffing.
But be carefull not to overstuff the cabinet since you will get a liveless reproduction
with to much stuffing...

[Timn8ter]

Originally posted by knorke
Since you have foam and fiber stuffing I would put a piece of foam on the backwall
and fill the rest of the cabinet with fiber stuffing.
But be carefull not to overstuff the cabinet since you will get a liveless reproduction
with to much stuffing...

That sounds like a good plan. The foam will help reduce reflections from the back wall to the cone and the fiber will create a "virtual" larger volume. Hard to say how much fiber but I suppose you could start with .5 lb per cu. ft.