Bass trapping question


Hi,
I'm trying to use bass traps to enhance the sound of my room. I'm using Ready Traps wich use Owens/Corning 703 and their custom made cloth bags to do my trapping. My question is:

Will moving wooden bookshelves whose backing is made of 1/8 or less wood,(and of course with books/records/CDs prevent the traps from doing their jobs if the bookshelves are placed in front of them across each back corner?

My guess is that they would not trap the high frequencys but diffuse them while the low frequencies should pass right on through into the trapping material.

What do you think?
128x128sgr

Showing 2 responses by shadorne

If you straddle the corner with an impermeable barrier like the back of a bookcase then you have created a helmholtz tube resonator - the 703 behind the bookshelf will broaden the Q of the trap. I'd definitely take some before and after measurements as this may or may not be a beneficial effect, as you are converting a broadband absorber to a tuned absorber with a narrow bandwidth...
If I took the traps out behind the shelves would that still cause a helmholtz resonation problem.

It will make the resonance worse (sharper Q) - an easy way to deal with this would be to simply pull the bookshelf out so it is at least 3 inches from the walls (that should make it leaky enough to kill any resonance). The only problem would come from placing the shelves up against the wall (creating a triangular tube resonant cavity with an opening at one end)