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Is this material suitable for damping an alpair 7P /12PW cabinet?

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Hello everyone,

Now that my A7P/A12PW combination is slowly coming together, it is time to shop for cabinet damping material. I have a specific material in mind, a plate made of polyester wool, which is this:

http://www.merford.com/media/191560/akotherm-basic.pdf

The datasheet is in Dutch, but the absorption versus frequency chart should be easy to find. I am looking at the D40 (40 kilograms per cubic meter) variant, in the thicknesses 20 and 50 mm. Of all the absorption materials that have their absorption coefficient specified in a datasheet, this particular material seems to beat all others in the low- to mid frequency range at a given material thickness. Egg-crate and pyramid foams don't even seem to come close. The stuff that is sold at loudspeaker component shops has lower density, and thus probably poorer LF and MF absorption, but I have so far not been able to find meaningful data on any of those materials.

So I think I have found a promising material to damp a vented cabinet for an Alpair 12PW and a closed cabinet for an Alpair 7P. Or am I missing something?

Thanks for any input.
 
Hi,

There is maximum density of the stuff that lines speakers
that if you exceed it, it reduces effective internal volume.

From a translated page the D20 version is recommended for speakers.
40mm of D20 is better than 20mm of D40.

Makes sense for lining a vented cabinet. For sealed simply stuff
with polyester stuffing, vary the density, optimum is when the
minimum Fbox is indicated on the impedance trace.

rgds, sreten.

For small sealed boxes about 2.0 lb/cuft of polyfill should work.
The bigger the box the lower the optimum stuffing density.
 
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