Axiom Home Page Forums General Discussion Advice from Axiom Owners Help a newbie with deciding m60s m80s

I agree with the comments above, you're room is pretty big. Keep in mind that the M80s have enough bass for most musical types. Since you're doing 50% HT, I would focus on getting a sub that can deliver significant output down at least to 20Hz which usually means bigger enclosure and higher price.
If I wanted to go dual subs in this price range, I would consider the new HSU VTF-15H. People that own them are extremely happy with them.