Absorbers in low ceiling studio

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Davidlavin
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Absorbers in low ceiling studio

Post by Davidlavin »

Hi-
Things are really coming along here, and the construction is essentially done, and ofcourse, the room sound pretty bad.


fist the basic dimension of the room:
It is basically a trapezoid. two parallel walls one is 11foot 4 inches long, and the other is 17 feet. The other walls, one 11 feet 10 inches ( and basically perpendicular to the two parallel walls, and the diagonal wall is 12 feet long. The ceiling height is 80 inches, though thefloor slope a bit,so it isn't entirely parallel. I think that is really where my problem is. The construction is two layers of5/8 sheetrock on steel studs with rockwool. Double wall constructionto the CR, and the ceiling is sprung on RC.


I've started building some broadband wall units -basically 3 ' rockwool in wood frames coverd in fabric which I'll mount to the wall ( about 3 ' off the wall)

That has helped some, but I think the problem is the ceiling. I'm not eager to put up those panels on the ceiling b/c it is so low already. I was going to put in a pergo/laminate floor, but riight now it is just carpet over bare concrete.

I do have access to some old ceiling tiles. Would those help a great deal? Would putting thatlaminate flooring down hurt or help?

I've actually got my first client coming in next week, so I'm looking to do some quick fixes, and then I can get into more elegant solutions after that- obviously I'm not putting in a new floor this week, but I could put some temporary stuff on the ceiling,for example.

Thanks a ton as usual.

David
knightfly
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Post by knightfly »

For a live room, I don't recommend carpet on floors; bare concrete would be better. Carpet absorbs only high mids/highs, leaving you with too much mid for a "boxy" sound.

Step one would be to build enough of those absorbers (BTW, ' means feet, " means inches :wink: ) so they can be placed across all corners, 3 foot wide should be minimum - others, stood off the wall a few inches on one of the two parallel surfaces (flutter killers) - and, even tho the ceiling's low, you WILL need something up there - maybe a minimum 2" rockwool, that will be much more even absorption than carpet on the floor. Placing the absorption on ceilng instead of floor will help with any overhead mics and phasing/early reflection problems.

The fact that the floor-ceiling distances are NOT parallel may help a bit with flutter, but for that to work by itself you'd need at least 6 degrees out of parallel...

For more permanent floor, you may want to look into stained concrete; this can look pretty cool, and won't raise your floor making your headroom even worse... Steve
John Sayers
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Post by John Sayers »

Yes - stained concrete can look cool.

The pattern on the attached pic was created with a concrete cutter before staining.

cheers
john
Davidlavin
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Joined: Sat Jul 19, 2003 8:10 am
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ok, getting clearer

Post by Davidlavin »

I'm all set to build some more of those panels. You said they should go on the parallel walls only? should I not bother with the non parallel?


As for the corners- the rockwool I've got is 2' x 4' - why do I need it to be 3 feet wide?

The thing I can't believe is the bare concrete. I mean, with that bare, it is like a- well, a concrete room. Sounds like a warehouse.

What about the ceiling tiles as a temporary fix? And if I'm going to put up some of those panels on the ceiling, can I put them here and there, or do they need to be everywhere?
also, is rockwool my best choice? there are a lot of posts here about a number of products. would something else inthe same ( or lower) price range be better?


Thanks Steve, especially for the speedy response.

David
knightfly
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Location: West Coast, USA

Post by knightfly »

I'm all set to build some more of those panels. You said they should go on the parallel walls only? should I not bother with the non parallel?

Actually, you should do the parallel walls FIRST, and if there's a panel on ONE wall, the OPPOSITE one should be bare; alternate them. For the parallel walls, you may also need panels, just to get enough absorption in their particular frequency range; too soon to tell. I only know you WILL want them on the PARALLEL surfaces as described.


As for the corners- the rockwool I've got is 2' x 4' - why do I need it to be 3 feet wide?

Because 2 feet across the face isn't always going to get you enough effect, and you're in a hurry (client coming), and because 4 feet wide will probably eat too much of your space. You could always try the 2 foot width, and if/when it's not enough add another layer in FRONT of it.

The thing I can't believe is the bare concrete. I mean, with that bare, it is like a- well, a concrete room. Sounds like a warehouse.

Of course it does; it's untreated, remember? But carpet isn't going to give you anywhere near an even absorption. Corners, ceiling clouds, and offset patches WILL; you just need to figure out how MUCH and WHERE, which is what I'm suggesting as a STARTING point.

What about the ceiling tiles as a temporary fix? And if I'm going to put up some of those panels on the ceiling, can I put them here and there, or do they need to be everywhere?

Here and there is a good start; if you do a fairly large section of the room and leave the rest of the ceiling bare, you can do some test recordings and compare.

also, is rockwool my best choice? there are a lot of posts here about a number of products. would something else in the same ( or lower) price range be better?

From all reports, rockwool IS the low priced alternative; nearly identical absorption characteristics as OC 703, except typically HALF the cost and they will actually SELL it to you; however, you're right there ARE several products mentioned; for the most part, a given thickness and density in nearly ANY of these will perform almost identically. Brands like Roxul, Certainteed (Johns Manville), Insul (Australia mostly) USG (SAFB's, or Sound Attenuating Fire Blankets), all will work acoustically.

From an installation standpoint, if you're hanging clouds the 3 pcf rockwool products tend to be a bit more rigid, so may be easier to keep looking good.

I posted one method of hanging these on a RC ceiling today, it's here -

http://www.johnlsayers.com/phpBB2/download.php?id=4620

Thanks Steve, especially for the speedy response.

You're welcome; your timetable seems to be a bit pressing, and I had a few extra minutes so it worked out... Steve

John, the stained concrete looks so cool I may give it a shot in my new digs - Jake Owa's a "paint-meister", and has recently moved to the Northwest from Hawaii; I may give him a shout about this...
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