Ceiling Tiles and acoustic wall panels

[PinkHumpy]

Hey all,
I was just looking at some OC 703 alternatives as I just moved into a house and have an untreated small spare bedroom as a temporary mix/recording spot (finishing basement). I want to make some basstrap panels to prop up temporarily so I can finish my new demo. Check this out - according to absorption info on this site, armstrong ceiling panels may be better than 703? - http://www.bobgolds.com/AbsorptionCoefficients.htm

Can this be right? Armstrong ceiling tile (at probably around 1" thickness) absorbs more than 1" thickness of Owens Corning 703? I wonder what 3" thickness of these ceiling tiles would do for a bass trap or room treatment, as an alternative to 3" 703. Now, I have no clue what these ceiling tiles cost. I was just really surprised by the stats:

---------------------------
Product
125hz 250hz 500hz 1000hz 2000hz 4000hz NRC

Cirrus Beveled Tile (armstrong - site doesn't specify thickness, but I assume it's 3/4" standard?)
0.38 0.38 0.51 0.77 0.89 0.95 0.85

703, plain 1" (25mm) on wall 3.0 pcf (48 kg/m3)
0.11 0.28 0.68 0.90 0.93 0.96 0.70
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On a separate note...
I wonder if these acoustic wall panels could be used in a open space (without covering the back to prevent itchy fibers from getting into the air). It's supposed to have an acoustic transparent membrane, and 1.00 max NRC at speech level (no data on different frequencies though).
http://www.armstrong.com/commceilingsna ... e2210.html

Cheers,
Brendan

[z60611]

Ceiling tiles are often mounted with 16" of airspace above them, which may account for the increased LF performance.

This document http://www.armstrong.com/common/c2002/c ... s/2823.pdf says E400 mounting. The 400 is milimeters, so that's 15.75"

In other words, the two tests may not be comparable. Or to put it another way, have a look at what happens with {703, plain 1" (25mm) 16" air }

[Silicon Audio Labs]

Home Depot - Post hole tubing (cardboard) goes up to 2' in diameter.

Wrap 'em (spray glue) with acoustic fabrick.

Knightfly, what's the quick n' skinny on these things as far as filling them with fiberglass, cloth, rocks, nothing?

[knightfly]

Silly-con, is this a non-sequitur or am I having a brain aneurism?

Are you asking about building tubular Helmholtz absorbers with these, or??!? Steve

[Silicon Audio Labs]

"...I want to make some basstrap panels to prop up temporarily..."

Cut 'em *length* wise - can get about 4 panels out of a one footer maybe more. More from wider ones.

Spray *some* with glue then apply fabric. Maybe paint for the others. Randomise some a bit.

Make some thinner towards the center of the wall, others thicker towards the corners. Fattest ones (or whole ones) in the corners of the room.

Prop them temporarily.