Atmos advice for slanted ceilings

[Ob1kinoB]

Hello Everyone,
Apologies, in advance, for a long post. Thought you would need details of my theater to address my questions.

I find myself somewhat ( totally ) confused on Atmos ceiling placement due to the geometry of my space. Therefore, I decided to approach those with much more experience than I for some clarifications and advice.

Theater Specifics:
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I have a bonus room over a garage that is 22’ x 12’-9” wide.  I will build out a false wall roughly 24”-25” out from the end wall and mount my screen.  So that leaves me roughly 20’ to work with.
I am going to do a 115” AT screen (Seymour Centerstage Xd) and have one row of 3 seats positioned about 9-11 feet from the screen. Will shift around until I get the best sound. Trying to avoid being in the center pf the room. Behind the first row of seats I am building a bar (18”-20” wide) and will add 3 stools behind it.

My goal is to assemble a 7.2.4 system.  The Atmos speakers are the 8” round Micca M-8c.  The rest of the speakers are all Hsu HB-1 mkII’s.  Now, here is my confusion....

I am familiar with all the recommended angles and positioning for the (4) Atmos speakers. HOWEVER, my room has angled ceilings.  Imagine the old style “Dutch” barns. (See attached photo). Npte that is not my room photo but my room is identical.

So my side walls go straight up to 61”-62” high then start angling inwards so that there is only 82” flat on the ceilings.I have read that you should try to align your Atmos speakers along the same lines (width apart)  as your mains.  But my mains are 96” apart yet I only have 82” flat on the ceilings.

Question 1:  should I mount my Atmos only on the flat part of the ceiling and forego aligning with my main left and right?

Question 2: if mounting on the angled part of the ceilings do the rules about placement/location change since they are now essentially angled down towards the listeners?

Bonus Question: in my 7.2.4 set up the side surrounds have to be placed no higher than 48” off the floor since they are 14” and then the horizontal walls start angling inward.  That leaves them only about 33”-38” from the end listener.  Will that “locate” the speaker too much for the listener. Iif that is not desired would it just be more advisable to do a 5.2.4 system?

Whew!

I know thats a lot to read and I apologize again but my build progress is at a standstill due to my confusion. Any advice, thoughts, recommendations based on experience would be greatly appreciated. 

[Ob1kinoB]

Hi folks,

No advice, impressions from anyone?

Not a problem. Its a very specific issue but “Bonus” rooms are common throughout the South and most I’ve seen have angled walls. Therefore, I thought it might be of interest to others.

In the meantime, here’s what I’ve done to address my concerns.  I went to the RSL Speakers web site and ordered a set of their C34e round ceiling speakers.  These speakers set the drivers at a 15 degree angle which i believe will certainly help my issue.

Btw, I posed these questions to Roger from RSL and his recommendation was to mount the C34e’s in the slanted ceiling and point the angled speaker baffle at the main listener position.  That will be my approach and kudos to him for taking the time to assist me and provide the benefit of this knowledge. 

Cheers,

Hugo

[David Vaughn]

Hi folks,

No advice, impressions from anyone?

Not a problem. Its a very specific issue but “Bonus” rooms are common throughout the South and most I’ve seen have angled walls. Therefore, I thought it might be of interest to others.

In the meantime, here’s what I’ve done to address my concerns.  I went to the RSL Speakers web site and ordered a set of their C34e round ceiling speakers.  These speakers set the drivers at a 15 degree angle which i believe will certainly help my issue.

Btw, I posed these questions to Roger from RSL and his recommendation was to mount the C34e’s in the slanted ceiling and point the angled speaker baffle at the main listener position.  That will be my approach and kudos to him for taking the time to assist me and provide the benefit of this knowledge. 

Cheers,

Hugo

Hugo,

I saw the post but forgot to respond. I like what Roger is suggesting. I have Atlantic Technology speakers for my Atmos speakers that do the same thing. My ceiling was slanted as well, but I ended up flattening it out

[AVSMike]

How wide is the flat area?

[AVSCraig]

I have angled ceilings in my theater too, but with a peak that's 11' high I went with small surface mount shelf speakers ( Martin Logan Motion 4's ) surface mounted. They can be pointed where I want them. Your ceilings look lower though, so I'm not sure that is as good as what you wound up doing. 

[Ob1kinoB]

Hugo,

I saw the post but forgot to respond. I like what Roger is suggesting. I have Atlantic Technology speakers for my Atmos speakers that do the same thing. My ceiling was slanted as well, but I ended up flattening it out

David,
thanks for your reply.  I have high hopes that the 15 deg angled baffle in the RSL’s will solve my concerns. At the end of the day, any Atmos sound will be better than what I have now which is none. 

As for Roger from RSL I found him to be very friendly and willingly helpful which is great in this industry.

[Ob1kinoB]

I have angled ceilings in my theater too, but with a peak that's 11' high I went with small surface mount shelf speakers ( Martin Logan Motion 4's ) surface mounted. They can be pointed where I want them. Your ceilings look lower though, so I'm not sure that is as good as what you wound up doing.

Mike and Craig,

My ceilings are 96” high at the flat area. The flat portion of the ceiling is 82” wide and runs the length of the room which is 22 ft long.  

Craig hit on the very thing that concerns me with this room. If the entire ceiling was flat at 96” high I would not be concerned all.  The fact that there are angled walls lowers the ceiling space and makes placement of side and rear surrounds as well at Atmos speakers more of a challenge. 

The angled ceiling also impacted the width of the screen I could do since it becomes a matter of width versus height off the floor.

Thank you all for your input. I will report back later on the outcome. Am painting walls now and carpet comes early next week. The snowball is starting to roll down the hill....

[AVSCraig]

Mike and Craig,

My ceilings are 96” high at the flat area. The flat portion of the ceiling is 82” wide and runs the length of the room which is 22 ft long. 

Craig hit on the very thing that concerns me with this room. If the entire ceiling was flat at 96” high I would not be concerned all.  The fact that there are angled walls lowers the ceiling space and makes placement of side and rear surrounds as well at Atmos speakers more of a challenge.

The angled ceiling also impacted the width of the screen I could do since it becomes a matter of width versus height off the floor.

Thank you all for your input. I will report back later on the outcome. Am painting walls now and carpet comes early next week. The snowball is starting to roll down the hill....

I think with modern room correction, speaker placement is more forgiving than not. After all, who has a layout like Atmos shows - a round room with one sweet spot seat in the middle ? I'm sure it will sound great, and I bet you can't wait to get finished !

[AVSMike]

Mike and Craig,

My ceilings are 96” high at the flat area. The flat portion of the ceiling is 82” wide and runs the length of the room which is 22 ft long. 

Craig hit on the very thing that concerns me with this room. If the entire ceiling was flat at 96” high I would not be concerned all.  The fact that there are angled walls lowers the ceiling space and makes placement of side and rear surrounds as well at Atmos speakers more of a challenge.

The angled ceiling also impacted the width of the screen I could do since it becomes a matter of width versus height off the floor.

Thank you all for your input. I will report back later on the outcome. Am painting walls now and carpet comes early next week. The snowball is starting to roll down the hill....

I would probably locate the atmos speakers on the flat. You will be giving up some width, but gaining height and on an 8' high ceiling, you really do not want to be giving up height. If placed on the slope, you are not going to have much vertical separation between the lower surrounds and the atmos speakers. Place as wide as you can on the flat. You should be able to get close to 6' center to center spacing for width.

[Ob1kinoB]

Craig, you and I are of the same thought in that the Audessy x32t adjustments will help out. My further thought is “hey, its the Atmos channels and a lot of movies wont even make use of them so no point in obsessing too much over this.

Mike, thanks for your recommendation. Roger from RSL did recommend mounting on the angled ceiling so that I could try to stay aligned with the front channels as per the Dolby recommendations. But, he said to place them as close as possible to the flat part of the ceiling. So in that, he lines up with your thoughts on not losing any height. 

So, based on my comments above about not obsessing too much and the height recommendations I will mount on the flat portion of the ceiling, as wide as possible, and move on. 

Btw, the speakers arrived today and they look great and are of a much higher quality than what I was thinking to use. So, either way, I’m glad to have gone through this exercise.

Hugo

[AVSMike]

Craig, you and I are of the same thought in that the Audessy x32t adjustments will help out. My further thought is “hey, its the Atmos channels and a lot of movies wont even make use of them so no point in obsessing too much over this.

Mike, thanks for your recommendation. Roger from RSL did recommend mounting on the angled ceiling so that I could try to stay aligned with the front channels as per the Dolby recommendations. But, he said to place them as close as possible to the flat part of the ceiling. So in that, he lines up with your thoughts on not losing any height.

So, based on my comments above about not obsessing too much and the height recommendations I will mount on the flat portion of the ceiling, as wide as possible, and move on.

Btw, the speakers arrived today and they look great and are of a much higher quality than what I was thinking to use. So, either way, I’m glad to have gone through this exercise.

Hugo

It is good if you can have the atmos speakers the same width apart as the mains. It is okay if the atmos speakers are not quite as far apart as the mains. It is not okay if the atmos speakers are farther apart than the mains.