Two surprising things I found that improved my imaging and staging...

In my listening/TV room l have my two channel & 5.1 HT systems in a low console My room has vaulted ceilings and my listening position is eleven from my Maggie’s l have six feet from the center of my speakers to the side walls For critical listening l grab my tape measure and position my Maggie’s four feet from the wall and nine feet apart with slight toe in All measurements are within + - 1/8 inch and symmetrical
Typically l find this setup to give me the best
soundstage with excellent inner detail I’ve tried numerous speaker locations so don’t be afraid to experiment I have located my speakers twelve feet apart and six feet into the room and all over the map, just to hear the results and confirm if l have my speakers in the best position Now when l get real bored l start messing with my two sub woofers locations, but not too often as they weigh 100 lb’s each!

I intentionally misspelled toe in as tow in to see if millercarbon would catch it and damn if he didn’t.  He had to be a grade school teacher in a past life because he never misses a misspelled word!

Glad for the mispell, intentional or not. Miller's wit gives me a chuckle.

I am in the equidistant camp and use about a 7.5ft triangle with the D2s and my ears (about 50" from front 20'w wall, 20wx17d room). Aimed just a bit, towed or toed, behind my head for disappearing into the music.

http://www.acoustic.ua/forms/calculator4.en.html

Here's a site where you populate in detail your room dimensions including ceiling height, the locations of you speakers, the height of the speaker drivers, your listening position, your seated ear height and the program will show you the 1st reflection points on all the walls, the ceiling and the floor of your room.  Good tool vs. the mirror method. 

Don't feel bad willy-t many have made the misteak of misunderestimating my intelagence.