I have two Martin Logan Dynamo 10" subs in an 11x20 room. I have the subs placed on the short (11') wall. From my experience, if you can make one sub work, you can probably make two work, but one will probably serve your needs in that size room. I would recommend a Velodyne SMS-1 sub equalizer to aid in integration. Also, I would recommend setting the low pass filter just below the lowest rating of your main speakers, so that the sub basically just fills in the low end. Also, show restraint in the volume control.
Two subs in a small room....
I have read that two subs smooth out the bottom end and give a much better sound. But, what if you have a room that is just not big enough for two subs. Is it worth the effort to get two "small" subs or is there a special placement for just one sub besides the usually place, behind one tower. What about placing the sub right in the middle?
By the way, my system is in a 10 X 10 room and it is in a diagonal configuration if you can picture that.
By the way, my system is in a 10 X 10 room and it is in a diagonal configuration if you can picture that.