I am slowing heading down the path of a new theater room. It's a conversion of a double garage which currently has no ceiling. i.e. exposed trusses and roofing. The room is pretty much square at 20 x 20

I have the option of fitting a regular ceiling at around the 9 foot mark or leave the trusses exposed and clad directly onto the roof. It's a pretty standard pitch ^ type roof. Guessing the high point at around 16 to 18 foot dropping to 9 foot over a 10 foot distance. (if that makes sense) The back and front of the room would be the low points.

I have a 7.1 system: 60s up front with 150, 8s all around and a 500 as the sub. Wouldn't think the extra room volume would make too much of a difference but that would be one of my questions.

I'm needing to rewire the electrics in the house and need to run wire through the room to my office which is why I need to make a call on this now. If I go regular ceiling, the wire gets pulled through across all the trusses on the shortest route, if vaulted I need to prepare for that and run accordingly.

I could go either way at this stage but was wondering what the great minds over here thought about the differences and if there was a definite winner with regards to sound. I know square rooms are sucky and was wondering what effect a vaulted ceiling would have on that if any?

Thanks,
David

All of the rooms I have seen with "glorious" sound have had vaulted ceilings, although there could be a bit of a placebo effect going on (I'm tall and slightly claustrophobic).

If the ceiling is going to be at a 45 degree angle (eg 12/12 pitch roof or similar) or even close I might stay away from it though, since a 45 degree vaulted ceiling introduces some of the same effects as a square room. Your use of ^ concerned me because that looks awfully like 45 degrees

The vaulted ceiling would take your room volume up from ~3600 ft^3 to ~5200 ft^3 which probably is enough to affect how much your sub can pressurize the room, but on the other hand the Axiom DSP subs can probably handle the extra volume more gracefully than most.

Did your username come from the band (one of my all time favorites), or from somewhere else ?

The vaulted issue is out of my league, but I'd assume imaging would be great as the reflections will be naturally delayed and not hitting a parallel surface.

But the 20x20 issue can be fixed via a false wall at one end. At the construction phase it is easy and makes for a very nice and tidy set up.

Just looked at the architect's diagram and the pitch looks to be 25 degrees.

Username comes from a surfboard.

I would be a bit concerned if the sub was not able to pressurize the room adequately, although that would probably be a plus on the waf side of things...

Don't think a false wall is an option but it is a good thought.

25 degrees sounds great.

You can do a lot of cool things with a false wall, including having a place to store all the junk you probably had to take out of the garage and haven't found a home for yet

Then again, I guess a 20x20 room is at least going to be big enough to put the bass peak down somewhere useful (28hz IIRC), and the 500 is ruler flat rather than having a ~30 Hz peak like most subs in its range so it might all work out well.

Don't worry about the sub not being able to pressurize the room; I was just trying to make the point that the extra volume would be enough to make at least a small difference.

I guess the company wasn't named after the band either ?

With all the work and money on the build out, check around on the impact on sound with a square room. So much is said of the impact of the room that you should be sure you are not building a bad sound - too easy to fix at this stage.

Just my two cents, but I realize the world does not revolve around HT.

It's been a long day and my mind is clearly wondering bridgman. Not sure the origin of the name to the surfboard, could quite possibly be the band. I just really liked it. The company I worked for was Canned Heat which was also a band, hence the confusion

Where I live all our walls are brick and plaster, no drywall, so false walls are not the done thing really. Everything gets chased into the walls with angle-grinders and conduit so getting it right first time is important. Also with where the windows are it will not really work.

I'm just throwing this out there, but as far as I can remember I've never been in a movie theater or opera house/theater that's had vaulted ceilings. Of course their ceilings are very, very high, but not vaulted. Makes me wonder if a level ceiling is possibly more desirable for sound?

So the decision has been made and a regular ceiling it will be. (When I get to install it that is

Thanks for the comments and feedback. This is such a great place to bounce ideas around.
Much appreciated.

See, now I would have guessed that a vaulted ceiling was required when you have "Curved Air".

I am no expert, but I think if I were in your shoes I would stick with the architects plan to put a 25 degree pitch in the roof. From what I have read from Ethan Winer (Real Traps), irregular shaped rooms sound better because of the varying angles of reflection and he said that he preferred angled ceilings as well.

that is correct David, I think I would also opt for the vaulted version.

I wouldn't.

I've had two many experiences with rounded, arched ceilings in churches acting like a big parabolic reflector. There's a Greek church I used to work in pretty often, where, if you stood in one corner, you could hear someone whispering in the other corner 150' away....as if they were whispering in your ear!

Cool, sounds like what happened in one of the Indiana Jones movies.

Kinda cool at first, but setting up mics for good sound in that church was a b**ch!

I can relate, when my oldest boy's school added a new gym they had nothing to break up the reflections. You could be 10 ft from someone and have a heck of a time understanding what they asked you.

I don't understand these damn kids these days either.