My rule of thumb is that for regular TV, use a 3:1 ratio and for HT, use a 2:1 ratio.
(i.e. If sitting 12 feet from the screen, use a 48 inch (4 feet) for regular TV, and if for HT use a 72 inch (6 feet).
A 3:1 ratio for HT is just not quite like being in the theater, IMHO. Unfortunately, I have a 3:1 ratio at home, (46" TV @ 12 feet) and while it is okay, especially for TV, it is not quite good enough on moives to convey that feeling of being in the theater. But then again, I prefer to sit about 1/4 of the way back from the front seats in the theater, wo we appear to have a different perspective on watching movies.
That being said though, if you're getting a headache from being too close, you should take that into account. My guess is that you should keep to a 3:1 ratio, (at most), which means that your 56" is just a little too big. (Perhaps we should trade your brand new 56" DLP HDTV, for my 4 year old 46" RPTV? No, huh?!)
My two cents worth anyway.
Good Luck in your quest!
(i.e. If sitting 12 feet from the screen, use a 48 inch (4 feet) for regular TV, and if for HT use a 72 inch (6 feet).
A 3:1 ratio for HT is just not quite like being in the theater, IMHO. Unfortunately, I have a 3:1 ratio at home, (46" TV @ 12 feet) and while it is okay, especially for TV, it is not quite good enough on moives to convey that feeling of being in the theater. But then again, I prefer to sit about 1/4 of the way back from the front seats in the theater, wo we appear to have a different perspective on watching movies.
That being said though, if you're getting a headache from being too close, you should take that into account. My guess is that you should keep to a 3:1 ratio, (at most), which means that your 56" is just a little too big. (Perhaps we should trade your brand new 56" DLP HDTV, for my 4 year old 46" RPTV? No, huh?!)
My two cents worth anyway.
Good Luck in your quest!