ceiling angle and height...

[jordya]

Hello everyone,

I have posted this question in a previous post in the construction section, since I am still building the room. I am also posting it here to see if anyone has any feedback.

To sum it all up, I am building a control room (13' long X 11' wide X 12' high) and I want to build an angled ceiling in it. The ceiling will start at 8' in the front (mixing position) and go to 10' in the back. Click here for the pictures and other info regarding the space. http://www.johnlsayers.com/phpBB2/viewtopic.php?t=4558

My question to you is should I continue with this plan, or would it be wiser to start the ceiling height at 9' and go to 12' in the back, or any combination thereof. The ceiling construction will be double sheetrock, soundchannel and insulation.

Any help is appreciated...

thanks,

Jordy A.

[AVare]

Assuming your have done ray trace analysis for the listening position, the second choice gives a closer avaerage to the 11' minumu suggested in the NARAS P&E wing surround document.

Andre

[jordya]

ok, that helps. No, I haven't done a ray trace analysis yet. What is it and how do you do it? So, if I go to 11ft in the back, should I keep the front at 9ft, to stay with odd numbers in my measurements?

[knightfly]

That's not necessary when you have non-parallel surfaces; odds are, for best elimination of early reflections off the ceiling, going from 9 to 12 feet will work better. It takes more of an angle to kill early reflections than it does to stop flutter echo, it's possible that even a 3 foot difference in 12 feet may not be enough for a true RFZ without using absorbent in a few places -

basic idea of ray tracing - check out about 2/3 down the page, here

http://www.johnlsayers.com/phpBB2/viewt ... c&start=60

For ceiling reflections, you would need to draw an elevation sketch and use the same methods to determine reflection points... Steve