I do have a center and a sub. The center placement is in the obvious place, in the center between the main front speakers, below the screen. The sub is a different deal though. I won't know where I will place that until the room is finished. The best way to place a sub is to put the sub in your primary seating position, crank out some good sub material and then walk around the room and determine where the bass sounds best. You then place the sub in that location. I learned that trick years ago when I started planning this project on one of these ever so helpful forums.Just curious do you have a center channel and Sub.. I didnt see them in the drawing???