Unfortunately there isn't a dealer near me so I haven't been able to listen to the Zu's.You are aware of the 60 day Zu Audio in-home demo program, right?
My first question is regarding my room size. It isnt an extremely big room.IMO, your listening area is too small to accommodate the Definitions. They need more than 6.5 feet between them to breathe, and they should be farther apart than 6.5 feet if you are sitting 11.5 feet away.
Distance from speaker to center sitting point: 11.5ft
Distance between speakers: 6.5ft
Wall on left hand side ~2ft from speaker
Right hand side is open for ~10 more feet
Speakers are ~1.5 feet from the back wall.
Hopefully this gives you an idea of the room. Do you think this would be big enough for the Definitions?
Consider turning the system around so the 16.5 foot wall is the short wall, and the 18.5 feet is the long wall. Spread the speakers 10-11 feet apart, pull them out from the back wall farther than 1.5 feet, and sit 11 feet away.
Otherwise, look into a smaller Zu model.