[rhyno]

i've a bunch of 703/705 panels that have the thin aluminum-type paper facing on the side against the walls. if i wanted to double stack 2 of the 703 panels, does this facing prevent the LF waves from traveling through it? should i remove this facing from the panel that will be closest to the interior of the room?
eg (where | = facing on panel, and X is panel)
before
 speaker -->  X| -->wall
if double stacked
speaker --> XX| --> wall
or do i leave the facing on each panel so it is:
speaker -->X|X|-->wall

(assume i'll be adding poly battling on the side of the panel facing the speaker to get HF absorption)

many thanks
rc

[bpape]

Side wall reflections should have the bare 703 toward the waves.  For bass control, put the membrane (FSK) toward the wave.  If you double it, you can do it either way but generally, FSK facing the room and facing the corner is best.

Bryan

[*Scotty*]

rhyno,If you want to improve the effectiveness of the panels put an airspace between the two panels equal to the thickness of the sheet and also space them off of the wall at least the thickness of one of the panels. When the sound wave goes through a transition from air to fiberglass and back again it looses energy and undergoes more attenuation than if it just stayed in the fiberglass and finally hit the wall behind the panel and was reflected.
Scotty

[rhyno]

bryan, i'm unclear. are you saying that the membrane should face the room when the panel is against flat walls, but the membrane should face the corner when the panel is in the corner (b/c the bass "wave's" origin is the tri-corner area). pls advise.

(the thought that i've my panels reversed is appealing...so much more tweaking to go)

tia
rhyno

[bpape]

What I'm saying is it depends on the application more than the mounting.  For side wall reflections or anywhere else you want the absorption to go all the way into the high frequencies, the membrane side should NOT be facing toward the room where the waves will be coming from. 

If you want a reduced amount of high frequency absorption, then have the membrane facing out into the room.  Generally, this type of alignment is in corners and potentially on the rear wall of the room. 


Bryan