ChrisWiggles

Ceiling Acoustics

I saw the other thread on basement ceiling acoustics, but it's more about sound insulation/isolation. I really don't care (well, not willing to) about sound proofing my HT room. It's a low ceiling, and after putting in a floor, and carpeting and the like, then trying to add in double layered floating ceiling or something isn't worth it.

Anyway, I don't have a picture, but it's easy to visualize. About 7 foot ceiling, and the HT will be oriented with the floor joists running across the width of the room. I was thinking of just leaving the joists exposed, and painting them a nice dark color. I was thinking that this would leave me with a nice diffuse sound from the ceiling, while all the joists block any direct reflections coming from the front speakers. If I put drywall up there, then I'd have to treat the ceiling to eliminate those first reflections, and i'm losing valuable inches of headspace, and just creating another acoustic problem that I'd have to fix.

Does that make sense, and what do the acoustic experts think, am i being logical?

Another option would be putting fiberglass in between the joists, and covering the ceiling with fabric, thus not losing any space, and it could serve as either a mid-high absorption up there, or I could use hard fiber boards and use the joist space as broadband bass absorbers. I could also put helmholtz resonators up there too.

And I was also pondering the option of something like ASC's walldamp, not for isolation purposes, but for bass absorption. Is this necessary(and worth the cost), or would this kill the bass in the room *too* much.

Thanks for the help and suggestions.

Steve Adams

Wow, good q's im putting up tbar acoustical ceiling, but i have over 8 ft of space. so i will be at 7'6" when done. I think the cloth idea sounds good. as long as its stretched tight and looks like a ceiling....

\"I did\'nt know she was a cop, I thought she was a hooker!\" (homer simpson)

Wayne A. Pflughaupt

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Dave Milne

I believe your thinking is "right on" with the first option. Preserve as much perceived ceiling height as you can by leaving it open. I'd probably go one step further and paint it a relatively light color... again to improve the feeling of spaciousness. The diffusion from the joists will be a good thing. You typically don't need much ceiling absorption if you have carpeting on the floor anyway. Use some wall absorption at the first reflection points from the mains and maybe a bit on the front wall --as well as some diffusion there too --and you should be in business.

ChrisWiggles

Yes I think I'm going to scratch the idea of filling the joist area. I will treat the front walls and side walls with some panel absorbers lightly. While this will be a dedicated theater, I am gearing it towards 2-channel, so it won't need to be as dead as a good theater.

Very specifically, I've got a big cold-air return spanning two joist spaces that will need to be sheetrocked over(this doesn't come down out of the ceiling, it's up within the joists) but it is from just above the listening position, and then foward a couple feet. Just behind this, and slightly just above/behind main position is going a CRT. It will look a little funny with one sheetrocked chunk running across the middle, and I may need to treat that peice for first reflections if it extends far enough forward, so I dunno.

Dave Milne

Hmmm... you could go for the "industrial look" and leave it exposed. Or, if you extend the "sheetrocked chunk" back a bit to cover the area where the PJ is, you can use it to cover up your mount/wiring etc.

BudK

I would insulate between the joists and then add 5/8" drywall. 5/8" isn't much and I think it would clean up the acoustics.... I would never leave open joists and you certainly don't want to paint whatever surface you have on the ceiling a light color... the darker the better for better video viewing.

ChrisWiggles

Yes, I was assuming a black, or very near-black flat paint in the joists if I left them exposed.