Help with this simple design question...

In a room that is 19 feet 7 inches long, by 13 feet 3 inches wide, and 7 feet, 10 inches high... that is going to be a live room and control room in one deal... Is it worth angling the walls? I've read that 12 degrees is needed for the angle to eliminate flutter echo without treatment. (I will still use broadband treatment, bass traps of course). If I use 12 degree angled walls from the back walls to the front walls, there won't be much space in the front in between the walls. I calculate that to angle the walls at 12 degrees for a 19 feet 7 inch deep room, the wall will angle in a little over 4 feet in the front (by monitors) from each side. That leaves only 5 feet in-between the monitors. Plus I will lose overall space. I'm looking to get a nice sounding control room... mostly concerned about being able to mix well. Is it worth angling the walls?? Or should I leave the it a rectangle and make sure there is plenty absorption behind the monitors, all corners, and first reflection points on the side walls and ceiling??

Instead of doing 12 degrees for each wall you can split that in half to 6 degrees for each wall. But I know I've read soemwhere on here before John says that's the bare minimun you can go is 12 degrees he has also said 15 degrees out of parallel is much better. So why not try 7 degrees for each wall and get as close to the 15 as possible. I've already figured it out from your back corner " being the zero point where you would start to angle your walls" you would only end up losing 2' 5 3/8" on each side leaving you with 8' 4 1/4" of wall space on your front wall. (CAD comes in handy sometimes) hope this helps!!!

I would keep with the splayed wall principle. The splay is usuaully required for the lateral distance up tot he monitoring position, not all the back. Also, consider using a sawtooth design for teh splayed sections. Andre

Thanks for clarifying the degrees thing... What do you mean by sawtooth? Can you point me to any pictures?

Is it better for isolation purposes to space your studs 24" OC instead of 16" OC?

To be able to carry the weight of the mutiple layers of sheetrock you need for isolation purposes you need 16 o.c. minimum spacing between studs. 24 o.c. couldn't handle the weight and would fail mechanically due to the ceiling weight on top of the walls

For designing rooms with angled walls.... how do you cut the drywall for the ceiling so that it fits exactly? Wouldn't it be better to do the ceiling first in this case? I've read that doing the walls first is a better idea, but that would make getting the ceiling right rather difficult...

While extra layers of gypsum on a frame do add weight, it's vertical so won't put much more strain on the frame - there are quite a few 2x4 double framed walls with 3 layers of drywall on each side, still standing. True, if you support a heavy ceiling on an inner wall frame, it might cause problems - here's my approach - First, it's been proven that more flexible walls (all else equal) give better isolation, so 24" centers are preferable from an isolation standpoint. Second, a double cap is mandatory. Third, a 2x6 frame on 24" centers with a double cap will support a second story, so should do OK with a heavy ceiling - it's still 24" centers, so leaves the gypsum more "floppy" for better isolation. Angled walls, etc - if you have room, you can angle your walls 1' in 8' - this gives a 7.125 degree angle, and all you need to trim the ceiling pieces is a long straight edge and a ruler. Measure in 1 foot from the edge at ONE end of an 8' panel, and to the corner on the other end, and voila - perfect fit, good flutter control, done deal... Steve

knightfly wrote:

While extra layers of gypsum on a frame do add weight, it's vertical so won't put much more strain on the frame - there are quite a few 2x4 double framed walls with 3 layers of drywall on each side, still standing. True, if you support a heavy ceiling on an inner wall frame, it might cause problems - here's my approach - First, it's been proven that more flexible walls (all else equal) give better isolation, so 24" centers are preferable from an isolation standpoint. Second, a double cap is mandatory. Third, a 2x6 frame on 24" centers with a double cap will support a second story, so should do OK with a heavy ceiling - it's still 24" centers, so leaves the gypsum more "floppy" for better isolation. Angled walls, etc - if you have room, you can angle your walls 1' in 8' - this gives a 7.125 degree angle, and all you need to trim the ceiling pieces is a long straight edge and a ruler. Measure in 1 foot from the edge at ONE end of an 8' panel, and to the corner on the other end, and voila - perfect fit, good flutter control, done deal... Steve

Would the side walls really be supporting the ceiling? I was thinking do the ceiling first (so it goes all the way to the side walls) but fastened to the ceiling with clips and hat channel. Then the walls would be built on an angle.. drywall up to the ceiling (with 1/2" open for caulking). If I use a 2X4 frame with 2 layers of 5/8" drywall on only 1 side (since my outer leaf will be the existing concrete walls), will I need to use an anti-sway brace? What will I connect it to? The concrete walls? Or the ceiling? And what is the best anti sway brace to use?

Would the side walls really be supporting the ceiling? I was thinking do the ceiling first (so it goes all the way to the side walls) but fastened to the ceiling with clips and hat channel. Then the walls would be built on an angle.. drywall up to the ceiling (with 1/2" open for caulking). In your case, no; the ceiling will be hung from RSIC's off your upper floor joists. For best isolation, alternating ceiling/wall/ceiling/wall is best. See the threads on caulking/drywalling in the REFERENCE section for pix. If I use a 2X4 frame with 2 layers of 5/8" drywall on only 1 side (since my outer leaf will be the existing concrete walls), will I need to use an anti-sway brace? Probably at least one, better two, spaced along the side walls - front/rear walls are short enough not to need them. corners will be self-supporting for sway once the frames are covered with wallboard. What will I connect it to? The concrete walls? Or the ceiling? Either - you might be able to adapt the design I gave Aaron (floating floor thread, REFERENCE section) I think it's about page 16 or so. And what is the best anti sway brace to use? Besides the Aaron version, Kinetics makes one to go from concrete wall to stud frame http://www.kineticsnoise.com/arch/psb.html HTH... Steve