How far and wide? NSMT speaker placement

Every room is different. I think my speakers are out four feet or so. Mine Sonus Faber speakers do well in my room with a 8’ equilateral triangle.

The imaging stopped at the wall until I hung a thick wool carpet on the wall behind the speakers. Then the imagining went back behind the wall. The absorption from bolsters along the floor / wall junction improved the imaging even more. You can see photos of why main system under my user ID. 
 

But every room and speakers are different. The place to start is probably a 7’ equilateral triangle as far away from the front and sidewalls as you can. “Cross the streams” 18” behind your head to start with toe-in. Then move out to perpendicular to the wall to stain the best soundstage vs central focus. 

I use angles and have front left and right channels at roughly a 30 degree angle from my MLP. Because my room is a bit narrow I needed to bring the MLP forward to about the center of the room. See:

@simonmoon 

that is cool!!!  thanks for including pics

@t_ramey 

I have the Model 100's!  

Thanks

They have powered woofers, right?, so they don't need near-wall reinforcement.