Axiom Home Page Forums General Discussion Home Theater Newbie Home Theater Room Size Question

Hello, all! I've been reading about Axiom speakers for a long time, but just discovered your forums. I'm new to the home theater world, and am currently planning on building a dedicated HT in my basement. I have a question on room size. I will be working with one side of our finished basement. Two of the dimensions of the theater will be fixed since I'll be working with existing walls: The ceiling is 7' with a tongue and groove drop ceiling already installed. The width is 10'4'" with paneling that I plan to paint and treat with curtains and/or acoustic panels as needed. However, I have almost complete freedom as to the length of the theater; I just need to decide where to build the back wall. I was reading about the 'golden ratios' for room size. Some of these calculations give an approx. 16' length. I was thinking more of 20' or so. Based on my existing height and width, any opinions on the length I should go with? I plan on using a front projector/pull-down screen set-up for the video. For audio, I'm planning on floorstanding M60s or M80s with sub, surrounds, etc.

Any ideas or opinions on how long my theater should be would be appreciated. I'll be working on building/finishing the room this fall/winter, but need to decide the dimensions.

Thanks all!

Howdy....

Mine’s 12’ wide by 16’ deep and it’s too damn small. My next HT will be 16’ wide and 24’ deep.

You will have to decide if you want one or two rows of seats first. But if you go with a single row, I’d still make it a minimum of 20’ in length just so you have room for proper 7.1 speaker placement, furniture placement, your equipment and storage.

Mine is 13' x 24. I wish it was a little wider, but works well. If you are limited by the 10'4" dimension, don't make the length a multiple of that (i.e. 20' 8"). Make it 23' or 24' if you want 2 rows. You'll need the space. Or 16' is fine if you are doing only one row.

Mine is 15ft x 31ft, that opens into an overall 31ft x 30ft x 9ft room. First row is 13ft back, followed by a second row on a platform. Behind that is all the kids toys and walkout door/windows.

Danno, welcome. If possible, avoid having the length almost exactly twice the width(or three times the height), since that ratio leads to a unfavorable concentration of room modes. 18' or 23' would be suitable lengths from that standpoint.

I played around with Modecalc (which you can download from the RealTraps site) and found that 17.5 feet and 25-26 feet seemed to give the best distribution of room modes.

Thanks, all! I was planning on two rows of seating, so it looks like I'll go with approx. 23-25 feet.

I'll keep reading and learning from your forum, and I'm sure you'll hear from me as my project moves along.

If you decide to go 23-25’, stick with 24 or slightly less. When building, always try to stay in four foot increments as all sheet goods come in four foot incremental lengths. Plus your framing is in four foot increments. If you go slightly over that four foot rule, you’ll cause yourself a lot of grief and wasted costs.

That's a good article and a pretty neat site.

Welcome Danno ! I'm in the same newbie boat as you with regards to construction of my HT. I must have lucked out .. didn't really know there was an ideal lxwxh ratio so to speak.

My dimensions are roughly 24'long (to front of wet bar) x 11'5" wide x 7'5" high.

Well, I don't know if this is the wisest approach, but three of the four walls in the area I'm converting is already studded and has paneling on it. I was planning on just priming and painting the paneling, building the new 4th wall the same way, then add acoustic panels at the appropriate places if needed. I was hoping to avoid the drywall dust/mess. I know there is insulation underneath the paneling, so I would think that would help with the acoustics a bit. I did this with a spare bedroom in the basement, added chair rail molding all around, and it looks pretty good (the grooves in the paneling actually added to the aesthetics.) I’m not sure how good/bad this would be for acoustics in a theater room, though.

Any thoughts on this approach?