Building a new house: need home theater size/depth advice

[remy123]

I am fortunate enough to be building a new home. My original plan was to have a movie room on the second floor above the garage, measuring 22 feet, by 15 feet, with 9 foot ceilings. After going to local high-end audio stores, I think i want to increase the depth of the room. For a reasonable amount of money, I can extend the depth of the room to 33 feet from 22 feet. Let me preface this: when I go to the movie theater, I like sitting in the rear of the theater. I don't like being too close. With a 22 foot depth room and a 119 inch or greater screen I fear I'll be too close for my comfort.

Is this a good idea to increase the depth of the room? Thank you for your help in advance!

 

[TLS Guy]

I am fortunate enough to be building a new home. My original plan was to have a movie room on the second floor above the garage, measuring 22 feet, by 15 feet, with 9 foot ceilings. After going to local high-end audio stores, I think i want to increase the depth of the room. For a reasonable amount of money, I can extend the depth of the room to 33 feet from 22 feet. Let me preface this: when I go to the movie theater, I like sitting in the rear of the theater. I don't like being too close. With a 22 foot depth room and a 119 inch or greater screen I fear I'll be too close for my comfort.

Is this a good idea to increase the depth of the room? Thank you for your help in advance!

33 ft is much too long for the ceiling height and room width.

For your room the optimal length is 24.3 ft. That will give you the optimal acoustic response.

Room ratios are seldom correct because most have to use an existing space.

With 9ft ceilings and 15 ft width, then 24.3 ft length is the optimal acoustic dimension, and that is what I would do.

That is pretty much the dimensions of my theater, except I'm a foot short on height and width compared to you. The room is excellent acoustically. If you go to 33ft it will upset the acoustic effect immensely.

It is acoustically excellent in both rows and the second row is plenty far from a 65" screen.

I would tier the second row. Some make a bass trap out of the second row base, I just made the base of the second tier acoustically dead. I do not have a bass problem, the acoustic balance is in my view optimal. However the speakers a critically damped transmission lines, which produce and accurate non resonant bass.

 

[BMXTRIX]

For screen size, the middle of a movie theater will have seats which are 1.5x the screen width away. With a 120" diagonal screen, you have a screen width of 105" - just under 9', which would make a typical 'middle of the theater' seating distance at 13.5'. I would expect at least two rows of seating, similar to above, and the front row likely around your 13.5' 'ideal' center distance, then a second row about 5'-6' behind that. Which would be considerably further back then 'center of theater'.

At this point, you fall in the minority, as many people are viewing at distances closer to 1:1 to 1.2:1 of screen width. A 120" diagonal from 10' viewing distance is more and more common as people like the immersion that it offers. But, as is always the case, this is personal preference. THX standards calls for the 1.5x screen width viewing distance as their standard.

To each their own on this, as long as the rest is good. For front projection, a dark room, with dark carpet, walls, and ceiling and proper light control is a must. Good projectors are a real plus, but good starts for not a lot of cash, and rarely gets better than the JVC RS series of projectors unless you go with the Sony 4K model. Don't get suckered into exotic projectors.

Frankly, if the cost wasn't to much, then I would likely add the extra footage (if the choice is not having it at all), then build a back wall at the proper distance and make the extra space storage. Put your equipment back there, lower the noise floor and light floor in your theater space. There is never a time when an extra 165 square feet of storage space is a bad thing. It's also a great place for that equipment.

Oh, and potentially you could build a false front wall and put speakers behind it with an AT screen.

 

[TLS Guy]

For screen size, the middle of a movie theater will have seats which are 1.5x the screen width away. With a 120" diagonal screen, you have a screen width of 105" - just under 9', which would make a typical 'middle of the theater' seating distance at 13.5'. I would expect at least two rows of seating, similar to above, and the front row likely around your 13.5' 'ideal' center distance, then a second row about 5'-6' behind that. Which would be considerably further back then 'center of theater'.

At this point, you fall in the minority, as many people are viewing at distances closer to 1:1 to 1.2:1 of screen width. A 120" diagonal from 10' viewing distance is more and more common as people like the immersion that it offers. But, as is always the case, this is personal preference. THX standards calls for the 1.5x screen width viewing distance as their standard.

To each their own on this, as long as the rest is good. For front projection, a dark room, with dark carpet, walls, and ceiling and proper light control is a must. Good projectors are a real plus, but good starts for not a lot of cash, and rarely gets better than the JVC RS series of projectors unless you go with the Sony 4K model. Don't get suckered into exotic projectors.

Frankly, if the cost wasn't to much, then I would likely add the extra footage (if the choice is not having it at all), then build a back wall at the proper distance and make the extra space storage. Put your equipment back there, lower the noise floor and light floor in your theater space. There is never a time when an extra 165 square feet of storage space is a bad thing. It's also a great place for that equipment.

Oh, and potentially you could build a false front wall and put speakers behind it with an AT screen.

A really good idea to take the extra space for equipment and storage. That keeps everything clean and tidy and makes for easy service.

 

[AcuDefTechGuy]

H:W:L Ratio

Sepmeyer: 1.0 : 1.28 : 1.54
Louden: 1.0 : 1.4 : 1.9
Volkmann: 1.0 : 1.5 : 2.5
Boner: 1.0 : 1.26 : 1.5

So it depends on which equation you use and all dependent on room height.

for 9' ceiling:
9 x 11.52 x 13.86
9 x 12.6 x 17.1
9 x 13.5 x 22.5
9 x 11.34 x 13.5

I'm doing a new house also. I am planning on 14' ceiling. Louden ratio of 1:1.4:1.9 would yield 14'H x 19.6'W x 26.6'L, so 14x20x27 would be the actual size.