How to tell if screen is accoustic?

Just got new speakers, and don't really have any place to mount my cs1. I used to have my speakers on top of the screen, but they were much smaller.

I have a mantle on my fireplace, I put the center speaker up there and truthfully, With the screen down, I feel like I still hear 80% of the sound 'through' the screen, with some sound going around the screen. Anyways, I see no discernable markings on the screen other than it is a 'richvision'. I mean, I guess I'm gonna run with the idea, really like how it looks, but I guess it would be nice to know for future reference.

Well, after watching the IU game last night (and ps, go hoosiers) I have come to two conclusions. 1: It is letting sound through, however, it is not a clean interupted sound, it is kind of muffled when listening to an announcer talk or any speaking parts directly, and 2, I'll have to go another route. Back to the drawing board...