A dome shaped underground studio....

Edi · Post by **Edi** » Sat Mar 29, 2003 4:09 am

Hi everyone. I´m new to this list and have been reading though the various posts. I am planning to build a studio in a one time Bunker which is totally underground and is totally dome shaped...33 square meters and about 2.55 m high at the centre with a diameter of about 6 metres. Yes, it´s like the upper half of a sphere.

any forseeable problems. Thanks for the help.

(John Sayers...you build great studios).

Post by **John Sayers** » Sat Mar 29, 2003 8:06 am

Edi - a dome is a series of parallel walls all focusing on the one point - the center of the room

You may have to break it up with additional panels.

cheers
john

J.J.McLeod · Post by **J.J.McLeod** » Tue Apr 01, 2003 3:25 am

I'm no expert, but I have to second John's statement. In fact, I think he may be sugarcoating it a bit. A sphere or half-sphere is absolutely the worst possible shape for any room used for audio. Not only is the sound focused into the center of the room (like two amphitheaters together, or a mirror in a large telescope), you'd also have horrible room nodes - standing bass waves that cause huge peaks and dips of 20db or more from one bass note to the next depending on your position in the room. All rooms have this problem to some extent, but if each dimension is the same, like in a cube, the problem is much worse. I suspect that a sphere would be almost unusable if you want any precision in the bass.

I think you have two choices. Build a shell inside the half-sphere (it might be too small, though) or find another space. Sorry to be so brutal, but I'd hate to think you went to all that work and still had a room you weren't happy with.

Good luck,

J.J.

J.J. McLeod
Different Drummer Studios
www.differentdrummerstudios.com

barefoot · Post by **barefoot** » Fri Apr 04, 2003 3:42 am

From a high frequency reflection perspective a hemisphere is bad. You definitely need to break up the focusing effect with panels like John said. The low frequency modes actually aren't nearly as bad as a cube. The nice thing about this shape is the primary room modes are not harmonic. This is psychoacoustical advantageous. Still the room modes will be rather strong and you'll have a difficult time taming them with such little volume to work with. The nicest thing is your studio will be quiet as hell.

Thomas