[Alan A]

Many thanks, in advance, for any responses.

I already have 15 four inch acoustic panels filled with 703 or eight pound mineral wool, covered with acoustic cloth. (My home theater room is 18' x 32' with brick in front and brick on one wall, and wood panels on another wall)

I am considering adding five more acoustic panels. These will be hung where I have spot lights illuminating the walls. The purpose of the lights was to illuminate my photography, and hang framed photos in those locations.

Now I'm considering printing my photos on photo canvas, and using the canvas as the cover on acoustic panels, rather than framed photos under glass.

Photo canvas is not porous. It is coated for printing. You can't blow through it. I assume it wouldn't allow high frequencies to pass through it.

My question is whether such panels containing 705 or eight pound mineral wool would still absorb mid to low frequencies? Since bass waves can penetrate walls, I assume the mineral wool should still function as bass traps and maybe even into the mid frequencies, even if the cloth covering is coated. I also assume that I'd be better off for this purpose to have the panels thicker at 4" even though 2" would look better for this purpose. But 4" would be better bass traps.

If this would work, I could still hang my photos on canvas, and get the added benefit of some sound absorption. A double benefit. That would, of course, be in addition to the 15 panels I already have, that would continue to be covered in acoustic transparent cloth.

Would it work? Would 4" panels, filled with 705 or mineral wool, but covered in non-porous and coated photo canvas, still absorb bass and mid-frequencies?

Or would they absorb zero, in which case photos in frames and glass, or photo canvas stretched on wood frames, would be a better idea.

Thanks again for any responses