I am 6'4" what I hear in my chair and what my wife 5'2"hears is a different presentation for sure, I slouch down a bit in my chair, and everything snaps into place better, but thing is moving your listening chair forward and backward till image and bass snaps into place. Forget general rules use them as a starting point but every room is different, I've heard open baffle speakers 2' or less from the front wall and they sound really good, tight forceful bass while the midrange was open, and the highs were extended and natural. This is why I am open to trying anything on speaker's placement till I learn how a speaker reacts in my room, It takes time, but you will be well rewarded, and you will really have a good ear due to the education on how the sound changes as you move them forward and back, closer together and toe-in, I go extreme then work my way out of it so I can really hear big changes that will happen then make the changes smaller and smaller till I lock them in a spot that sounds the best and when I think I have it, I might move them 1/4" in and out toe-in and if I lose what I had I know going back is the spot. Moving forward and back 6" at a time, if one way sounds better, I do the same back an 1" at a time, till they lock into my ear, then again move them just 1/2" if I lose the magic then I know which way to go to lock it back in. I do this over months, so I leave with it and get used to it, and then I make a change. I use 2-3 key recordings, vocal, small Jazz with strong standup bass, Piano, and lastly, classical that is well recorded. Once I'm happy then I am at the mercy of the recording quality but at least I know that and it's not my speakers or gear. I do focus on my room big time because that is the sound, we also hear as much as the speakers.