I hate to see you make a mistake due to some of the advice here. If you listen to music you will be much happier with the flatter FR and integration from 2 lower priced subs versus one higher priced regardless of your budget (as long as you are at a minimum quality level like the SVS you are considering). The improvement from the second sub is NOT about SPL's it is rather these other sound quality improvements and EQ alone will not get you there. You set the SPL's to your taste so you have no worries about being overpowered. The opposite occurs when you eliminate room modes via the second sub.
Regardless of what you are hearing this is not disputed in the scientific community. Do a little homework on room modes, nodes and antinodes and how standing waves behave below 60hz given that most room treatments have little effect in this range. You won't regret it.
Regardless of what you are hearing this is not disputed in the scientific community. Do a little homework on room modes, nodes and antinodes and how standing waves behave below 60hz given that most room treatments have little effect in this range. You won't regret it.