The most important factor in soundstage imaging

Excellent info everyone. I would say that the speakers (and placement) are the most important to imaging and staging and then the room (physical dimensions and treatment) and equipment moving backwards of importance and impact from the speakers. . . Of course none of this happens if the recording isn’t made well at a high bit depth with minimal processing and or brick wall filtered etc.

I am a firm believer that an active set up is the best way to deal with room nodes with multiple subwoofers that can counteract the inevitable issues that arise when playing music full range.

After all that, looking at adding BACCH as the pinnacle cherry on top to my system. Awesome innovation if you haven’t looked it up, applying all the science quoted above!

That BACCH system is fascinating. BUT- $54K is more than my mortgage balance. Glad I’ve been able to successfully apply the pertinent scientific/acoustic methods, mentioned above, for the past few decades. It’ll be interesting, to see how BACCH progresses, if the cost comes down and if it flies. https://www.stereophile.com/content/bacch-sp-3d-sound-experience and https://www.theoretica.us/faq.html

There have been many excellent general idioms presented.  But in the end remember that you should trust your ears and you will likely benefit from significant experimentation. 

By way of example, I have now adjusted my current speakers/listening position/sound absorption perhaps 100 times.  Some of these adjustments were mere centimeters.  I ended up placing the speakers on the long wall (which is not the standard recommendation as far as I can tell), with the speakers only 3 feet from the back wall (much closer than I expected), and my listening chair only two feet from its respective back wall (also a little uncouth).  Speakers are 6 feet from side walls so all absorption went directly behind my ears and behind (and between) the speakers.  I also placed a sound absorption panel on the floor in between the speakers and just slightly towards the front which made a noticeable difference in imaging/sound staging, which are two highly coveted qualities to me.  So basically I let the room distance mitigate side wall reflection and reduced back wall reflections with absorptive treatments, effectively increasing the direct/indirect sound ratio.

Play with listener height as well and consider buying a different chair (or sitting on the floor with cushions - tried that too).  Consider everything that is between you and the speakers - including ottomans which make a difference (in my case it had a negative effect).  Move components around as well (I like mine well off to side).  Consider speaker rake (I added a little positive rake with a footer delta from front to back).  There were massive changes in imaging/SS with speaker toe-in which is very speaker/room dependent.  Considering the degree of change, I spent a lot of time on this variable.

All this to say, my system setup looks way different than I expected and sounds better than ever.  Your's may as well if you experiment with placement variances of all components including sound absorption.  Which is why I do not plan on hanging my absorption (which will also make a difference as I will potentially hang it a few feet off the floor) until I graduate to my next (keeper) speaker.  

Have fun with the process and enjoy the music.

OP- you've gotten lots of good info from the above posters to work with. Jim (tomic601) has reminded me to mention to you what he and I both consider an essential guide to get the best possible sound from your system and that is Jim Smith's book Get Better Sound. Best $ you will ever spend to get results you didn't think were possible. Absolutely indispensable, IMO.

Tom

I think phomchick and others focusing on speaker placement and sound treatment are right on ..... I've been successful in several different spaces when I've had the flexibility to optimize.  In a living area, not so easy, but usually one can figure out how not to screw it up badly if you know what your are doing.

As to electronics, it seems to come from transparency, and that is mostly a factor in the quality of the passive components and age of the parts.

My 2 cents.