Are projector screens transparent to sound?

Thanks, Guys.
Any suggestions on where to get a good price on a stewart?

You might check Videogon or ebay. Do not buy a GrayHawk or a FireHawk. These were made for early LCD or DLP projectors with bad black levels. You want plain white 1.0 or 1.3 gain. the latter will give a slightly brighter picture without hot spotting.

AVScience has competive pricing on Stewart screens.

While Stewart doesn't make an inexpensive screen, the price difference may not be too interesting once you've specified the useful options : wide frame, light absorbing coating, and the 1.3 gain fabric.

I paid just a couple hundred dollars more for my 87x49" Velux Deluxe Stewart with Studiotek 130 than I would have a DaLite with the same options.

Also note that the big manufacturers including Stewart will build a screen to any size and shape you want. If you'd prefer 2.4:1 or 1.85:1 they'll do that.

The screen of choice should be the Stewart Screen.
I mounted mine away from the wall and have sound panels behind the sceen which are not visible but make a profound difference to the room. I also elected to to put sound panels beside the screen in my set up.
Back to the sceen, get the wider frame for the screen the one that has the flocking/velour finish on it. Any reflections will not show up with this frame whereas the metal frame with only the black paint will show the reflections. This would drive me crazy, well maybe crazier.
Good luck.

Just thought I'd update this thread with my recent experience.

I recently got a SeymourAV Centrestage XD dropdown 120" screen and it is extremely good. It is not totally transparent (none are) with a very slight attenuation mostly in the treble. I have not bothered to adjust my EQ as it is not a significant effect. Anyway for folks looking for an audio transparent screen this screen is unbeatable value - no moire at all. The screen was built to order with perfect precision, well packed (double boxed) and worked out of the box.

Now I have a TV for regular viewing and music listening with a dropdown large screen for when we want to watch a Blu-ray movie. The sound comes from behind the screen - just as it should or does in the real cinema.