I started this quest about 2 years ago. We were building a new house and got an unfinished basement so I could design and build the dedicated HT myself. I started by subscribing to a bunch of magazines and cruiseing through old issues I already had. Frankly most were not helpful, maybe once every six months they would have an article about home theater that was NOT product related. These typically delt with lighting or acoustic treatments, or maybe once and a blue moon something about actual construction. One magazine that was very helpful was Home Theater Builder magazine. I ordered all the back issues and got a 2 year subscribtion. The magazine is struggling and I believe has gone quarterly, but I would still order the back isses. just google them. I then found this amazing sight called Audioholics
The people here have been great in answering questions and providing advice. Another greagt resource is a thread over at Hometheaterforums:
http://www.hometheaterforum.com/htforum/showthread.php?s=&threadid=225610
I would read this thread front to back. It helped to prevent a LOT of problems. Basicall the thread is a series of responce of things people wish they had done or things they are glad they did do. It raised a lot of thing I never would of thought of, but of course would have realized later. Lastely I copied and modified a spreadsheet I found at sound and vision.
The attached sheet is used to develop the dimensions of the theater and seating distances. Manually enter information in the blue cells, all other cells are automatic calculations. Each blue cell has a comment telling you what to enter and what it will effect.
The first sheet "Room Dimensions" is split in two. The top (above the black line) are the quick and dirty calculations. The bottom (below the black line) are the ideal dimensions. There are no cut and dry answers - it will take some playing with numbers to get it all correct (or as close as possible). You may need to go back and change some numbers afterwards as well (for example screen size).
The second sheet allows you to fine tune your dimensions from the first sheet. Use the first sheet values as your initial values here. Keep playing with them until you get the best numbers you can. These calculations are sensitive enough that an inch or two can make a huge difference.
I can't stress enough the importance of good room design and dimensions. It will prevent an enormous amount of potential problems. Failure to properly design a room will result in very poor sound, requiring lots of effort (and cash) to rectify. Room acoustics are the name of the game.
After I did all my reseach and drew my schematics for the room I hired a HT designer and installer for a couple of hours ($75 and hour) to come the house and have me walk through everything I had. This was mostly just a sanity check to make sure I wasn't missing something drastic.
I had a blast designing and building my HT. I should get some pitcures up soon. Good luck and ask lots of questions.
