Theater Acoustics

[rjb]

I am building out an existing theater. My biggest problem is the fact that the room opens up in the rear to a bar area. I have had a theater in the existing space and I am now upgrading it. I really enjoy the way the room works with the bar area especially when entertaining during sporting events, so much so that I am willing to sacrifice acoustic performance. I am investing a lot in the new theater and I have a friend who is an systems integrator working with me. I enjoy the hands on work and have been doing all of the build out work myself with the help of a couple local carpenters and electricians. That said I have been going on the premise that I would make the theater area as dead as possible and just use a lot of power to make it sound good. After reading many posts here I am getting concerned that I may be making a mistake. I have attached a preliminary drawing of my theater, the bar and seating have been moved aft 12" since this drawing and the total room dimensions are 16' x 34'. In the forward 18' of the theater I am planning on using 4" of OC 703 on the walls between the columns, 2" OC 703 on the ceiling and screen wall. I am also planning on two 17" x 17" x 24" bass traps on the forward screen wall corners. There will be two subs on the screen wall and one on each side wall. Here is a list of equipment. A surround on each wall for each row and two rear surrounds (I am still debating whether to use direct firing or surround for the rear). The aft wall of the room has a fireplace on the theater right and 8' of drywall theater left. Beyond the 21' 9" on the theater right the room opens up into a game room.

Sim 2 C3x Projector
Stewart Cinecurve acoustically transparent screen 116" @ 2.35
DVDO IP 50 Pro
Crestron Preamp
Sherbourn 7/2100a amp
Triad Gold 6 LCR
Traid Gold 4 surrounds and rear?
Traid Silver 15 in wall power Subs (4)

Any and all input would be great. I will report back with changes made due to your suggestions and the results.

Thanks!

[bpape]

Welcome to the forum.

I'd seriously rethink your premise of making it as dead as possible and trying to get it all back with power. Power won't compensate for skewed frequency response caused by too much thin, high frequency only absorbtion. Your front corners to the side of the screen appear to be blocked off. I'd make that transparent and use some good broadband bass control. That's a large room and that's really the only place you have to do much of anything due to the layout.

Try to bring the decay time across the spectrum into line. More is not always necessarily better.

Bryan

[rjb]

Bryan,

Thanks! The areas on both sides of the screen will be transparent and that is where I am planning on adding the bass traps. I am setting the theater up so that we can remove some absorbtion as necessary, I guess what I really meant was initially as dead as possible.

Should I use diffusers on the side wall?

I really only have enough depth on the side walls for 4" of material and my understanding is most diffusers are much thicker, am I wrong on that?

Is there any suggestion as to something I might be able to do to the rear wall?

Richard

[bpape]

Effective diffusion down into the vocal range will in fact be more like 6" deep. For pure HT, you'll want to stick to absorbtion. Don't get too crazy with too much and spread it evenly through the space.

If you want a bit of both, you can make a series of 3.5" deep, 6" wide, 48" tall frames filled with absorbtion and space them every 6-8". The frames will act as crude well diffusers and you'll get the absorbtion spread out well without overdoing it in any one place.

Bryan