Since you don't have a clue to your room size it is a tough call. Just one SVS properly setup can have heart pounding bass!! These subs aren't for the faint of heart. As mentioned above the Paradigm 15's are nothing to sneeze at either. No comment on the Fathom I haven't heard it.
The safe bet is one until you get an idea.These subs are the real deal! Oh yeah ..the SVS isn't exactly a small sub.I haven't heard a small sub that could truly replace a sub with real volume. There's always a compromise some where..so pick your poison. Not sure how it will carry over with your wife. Performance wise..if she's an HT buff..she'll love it.
The safe bet is one until you get an idea.These subs are the real deal! Oh yeah ..the SVS isn't exactly a small sub.I haven't heard a small sub that could truly replace a sub with real volume. There's always a compromise some where..so pick your poison. Not sure how it will carry over with your wife. Performance wise..if she's an HT buff..she'll love it.