Unfocused Sound stage

My sound stage has gotten very very big. On some cuts between between a third and almost half way up the side walls. That might be great but the center vocals also spread across the stage. Instruments in the background seem to be stable and more defined.

I tried moving the speakers around. Had them in the "golden triangle." Moved them 6" up and back and closer to side wall as well as closer to the middle. Not much change. Changed digital cable and amps. I run a all tube pre-amp. Could this be a issue with a tube? Other ideas?