this is Interesting....

good to know !

http://www.gearslutz.com/board/showthread.php3?t=61842

So you look at those numbers and determine that 1 inch is better than 4 inch for your purposes?

Bill

Hey Bill,

That's a mighty big avatar ya got there!

Same performance ... at 4 times less Money !!

"those Numbers" happen to be done with tests,
that are done far better then I could hope to replicate,
with people More knowledgeable in that aria then I,
so yes I tend to take what they say with Weight.
that site is thrown around allot here as well, so IT must have truth to it...

So it states on that Bobgold site that =
= 1", spaced with 16" air
is the same as
= 4" , spaced with 16" air...
http://www.bobgolds.com/AbsorptionCoefficients.htm


If you know of a "better" site , with "Superior" testing methods ... I am all ears ,
...and would love for you to point me in that direction,
We all just want to know the truth from Myth...

all I asked was that, in looking at those numbers, you determined that the 1 inch was best for your purposes. I'm apparently not reading the numbers in the same way that you are, or you have some need that differs from my own.

Bill

JR,

I have posted this as well at gearslutz. The poster there doesn't really understand what he's looking at.

When you wall mount you look for the most performance for the dollar.

The same is true when you use a type "S" mounting (16" off the wall) (I'm pretty sure that's the "S" mounting)

When you look for "bang for the buck" you have to take into account not only the spacing - but the density as well.

So in a small tight room - in order to get the same performance with 705 (as in your example) you would have to use 4" of 705 (mounted on the wall) to acheive the same results (roughly) as 1" of that material with a 16" spacing.

But if you lower the density (and thus the expense) and compare the numbers:

.......125Hz...250hz ..500hz.. 1000hz.. 2000hz.. 4000hz
701 plain 4" .87 .1.14..1.24...1.17...1.18...1.28
705 plain 1" .68 .0.91..0.78...0.97...1.05...1.18


See - 4" of lighter density at 16" beats the heavier density hands down......

in fact - if you can afford the 16" space - look at 703 versus 705 - once again a big cost savings:

......125Hz...250hz ..500hz.. 1000hz.. 2000hz.. 4000hz
705 plain 1" .68..0.91..0.78...0.97...1.05...1.18
703 plain 1" 0.65..0.94..0.76...0.98...1.00...1.14

The numbers are almost identical - yet the 703 is almost 1/2 the cost.

If you are in a room where you can't spare the 32", and I say 32" because in a control room you need symmetry - and thus will have these mounted on both walls, then the 1" of material is virtually useless.

Try to keep everything in it's perspective -

Sincerely,

Rod

Yup. And down at 50Hz or so, the denser material will, IMO, do a better job. But since there is no lab certified down that low, you'd never know it. Now, if you're going to USE that space and use 8-12" THICKNESS, then you can use 1.5lb material and get excellent results.

Also, in the GearSlutz thread, someone posted that a corners has 16" of spacing. That's true, at 1 point. Over the rest, it's variable and the average is less than 8" so the 16" numbers don't really apply.

Bryan