Speaker distance

I’m in a rectangular room.  My speakers are 4’ off the front wall, 3’ from the side walls and a little less than 8’ apart.  My head is 8’ from my speakers, with ears in line with the tweeters. The back wall is about 7’ behind my head.

@aewarren , this is the correct response 

There is only one sure way to optimize speaker positioning in a room and it is by ear.

For a sealed design, the equilateral triangle or similar usually works great. Add a port, and the room interaction multiplies. For planers, it becomes even more complicated. 
 

I am sometimes surprised as to how the rules can be broken to good effect. In college, one year I set up my double Advents about two feet from my mattress (which was on the floor). I used to listen at night in my bed, my head two feet from the plane of the speakers, which were about 8 feet apart. It was immersive and holographic, with substantial sense of depth (my Marantz 7 preamp helped give the depth, along with my Ampzilla).

The best way?  Put your speaker stands on casters.  Otherwise it's too difficult to experiment, even if your speakers are 77 lbs. each like mine.  You'll find the threaded diameter of speaker stand feet or  spikes is 8mm, so you need a threaded stem caster size of M8.  There are self-leveling casters so after you find the right position you can raise the caster wheel so the caster rests on a solid foot.  It may raise the height of the speaker an inch or two but finding the right location for the speaker is more important.  Good caster wheels will damp vibrations on a hard floor.  

@eisen0169 

Making them movable while experimenting is a great idea. Although, I would recommend furniture sliders...like from Amazon. They are cheap, easy and very temporary. You ultimately want them on spikes (with or without the dimpled coins) or even better something like Townshend Podiums.