As an owner of this particular BEAST;
Let me be very clear, for music, or video, this
is a no B.S. 18" 1250watt. 3000 watt peak.
Flat at 11hz. True sub-woofer. Identical to the H.G.S. 18
When blended, completely disappears.
Check out the heavy surround on the Velodyne.
You say video only, I also have a CHT-15,
that was reviewed and rated above All others.
IMHO, given your room size, you would be better
served with the likes of a CHT-15 instead of
a FSR-18. It WILL be overkill.
You will NEVER be able to realize the FSR's full
ability, with such a small room.
Listen to the subs. at home if possible, that is
the only sure way to get the right one.
A good 12" or 15" will be plenty of solid foundation,
given your room size. Especially if it is a Velodyne.
I Love Music!