Panel Traps or Acoustic hangers?

Oliver Sheen · Post by **Oliver Sheen** » Wed Mar 12, 2003 8:35 am

I was going to post this on my "Loft/Attic" thread but I thought it might be better to start a new one as it may have more general appeal

On the SAE site there are two types of low end absorbers

panel traps and acoustic hangers. They both appear to me to do the same job althought the panel traps do it in far less space!!

Is there anything to choose between them John

Many, many cheers!

Post by **John Sayers** » Wed Mar 12, 2003 9:22 am

all I can say on this is that hangers appeared in the 70's when the loudness of bands turned acoustics around dramatically.

cheers
JOhn

barefoot · Post by **barefoot** » Wed Mar 19, 2003 3:11 am

The data that never seems to get mentioned with respect to absorbers is their absorption coefficient (efficiency) in their respective bandwidth. Of course, you can build a panel absorber with whatever resonant frequency you like. 10Hz? No problem! But in order to do this you need a very massive panel. Massive panels have more inertia and are, therefore, more difficult to excite. More difficult to excite translates to less efficient. The only way to make a highly efficient panel absorber is to use a very light panel in conjunction with a very deep cavity. In other words you need a lot of space.

There's no getting around it. If you want to absorb low frequencies, you need space. Absorbent hangers just help maximize the efficiency of a given space.

Thomas

Oliver Sheen · Post by **Oliver Sheen** » Wed Mar 19, 2003 7:39 am

How big is massive? I suppose the larger the panel the lighter and thinner it needs to be. Is there a formula for working out the optimum dimensions for a given frequency?

In such a small space(less than a meter squared) would I be better off with panel traps?

regards

Oliver

Post by **John Sayers** » Wed Mar 19, 2003 8:30 am

Nice post Barefoot - I agree completely.
Oliver - you have a lot of wasted space in your setup, what I mean by that is below say 4' you can't use the space for anything other than trapping. In your case I'd look at hangers or slots or both.

How did the dormer work out - got a drawing??

cheers
john