The Golden Ratio rules for room dimensions has long been refuted. See Dr. Floyd Toole's article on room dimensions and standing waves on Harman International's website. As long as you avoid a perfectly square room, you'll be ok.

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Here are a couple of articles to start you off. Do a google search on "Home Theater Building," and/or "Home Theater Dimensions," and/or "Home Theater Rooms," etc. You'll probably find lots of stuff.


Author of "Status 101: How To Keep Up In A World That Keeps Score While Buying Into Buying Less"