Trying to build a near ref. listening room? Help

If its double wall, then you have the option of making the walls non-parallel, which will help. A TACT RCS 2.2x might be a cheaper solution!
:-)

Not sure if this would work, but if your room is going to be a "room within a room" in the basement, if you could somehow build a small door into the wall behind where the rack is going to be, it would make changing cables sooooo much easier....

Keep the room parallel. If you do have a problem later there will be a predictable fix. I can attest that having angles at the ceiling wall junctions will greatly improve your sonics. I have found by accident that a lot of accoustic energy likes to stick on 90 degree angles and rear its ugly sound later. You are welcome to e-mail me for the degree of angle to be used. Based on your dimensions and volume. Tom

My wall sconces rattle at loud volumes. I had to silicone the glass diffusors to the metal parts of the fixtures to *minimize* rattle, but they still make their own noises.
David.

Your room almost has perfect dimensions according to the Golden Ratio developed by Fibonacci. This is a series of numbers which avoids resonance problems in the room. The ratio is 1:1.618. If the dimensions of your room start with 9 feet, then the others should follow this progression. 9x1.618= 14.56. 14.56x1.618= 23.56. Therefore, with a 9 foot ceiling, your room dimensions should be 14.56 feet by 23.56 feet. This also works for speaker position. Multiply the room width by .276 to get the distance from the speaker front to the near side wall. Multiply the room width by .447 to get the distance of the speaker to the back wall. This will give you a progressive ratio of 1:1.618. With a room width of 14.56 feet, the distance from your speaker to the side wall should be 4.02 feet. The distance from your speaker to the back wall should be 6.51 feet. The distance between the two speakers should also be 6.51 feet. To provide a proper 60 degree angle between the sweet spot and the speakers, the distance between you and each speaker should also be 6.51 feet. Using these distances will allow you to hear perfect sound imaging.
If you truely want a reference sound room, you can construct your room with the Iso Wall System from Acoustical Science Corporation or ASC. This system uses resonant sound channels, Wall Damp pads and strips which convert vibrations in the wall or ceiling into heat. This will eliminate the boom bass sound in the walls. Check out their website at asc.com. This is enough for starters. Good luck with your sound room!