So 12" wide and 12" deep, up against the wall. Hmmm. Soundstage depth will be limited, but you will have generous boundary reinforcement, which can be beneficial if the speakers are designed to take advantage of it.
Can you tell us the approximate room dimensions? How close to the corners will the speakers be? Is this room open into other rooms (open floorplan)? Tubes or solid state?
Thanks.
Duke