Limited soundstage between speakers

rrm, Your room dimensions are close to identical to mine. Our set up is a bit different in that my speakers are 5 1/2’ from the back wall and I listen on axis about 9 ft back (about 4 1/2 ft from the wall behind the chair . I’ve minimized side wall bounce and have irregular diffusing stuff on wall behind speakers. If you can you might try moving your speakers a bit closer to the side walls and increasing your toe in to minimize first reflections off the side wall. Toe in slightly in front of your head could help depending on the design of your speakers. Something closer to an equilateral triangle. It could/should perhaps give you a soundstage that fills the wall behind your speakers (assuming that the information is in the recording). Good luck.

Newbee mirrors what i have found...little wider soundstage moving apart and toeing in (over your shoulder) to remove 1st reflections...speaker from front wall measured by tweeter.I think too far from front can loose sound stage...read you dont want side/wall and front/wall the same feet apart.Moving your chair up into  Triangle/soundstage is another thing to try and see were imaging is best.Dont over dampen room...leave some liveness?

Spendor broacher advertising shows their speakers facing directly forward while their Frequently Asked Questions shows toe in aimed at each ear at the listening position which appears to be a very slight isosceles triangle.

Using a familiar or proper recording I'd begin with the manufacturers triangle instructions. Moving a wheeled office chair slowly nearer and farther after any location adjustment may offer you some insight in determining the staging.

My speakers were designed for wide forward facing. Using an approximation of the golden thirds speaker and listening positioning has yield massive staging and acoustical speaker disappearance in my very reflective room.  

You could hire an experienced dealer to do the setup. Best of luck with it.   

Personally, I would never purchase speakers that were recommended or required  to be toed in.

@laps ?

Ok, why?