Solid state amplifiers and sound stage, especially front to back "depth"

Skimming through other’s input I think there is another aspect that hasn’t been touched upon and that is the source recording quality. I’ve got a BAT VK-600 heavy duty solid state amp coupled with the BAT VK-5i tube amp with my Apogee ribbon speakers and I’ve found that more often than not recordings have excellent left to right, but truly great imaging that also have deep front to back complex spacing require a top quality recording engineer using the right equipment (particularly analog) and this is much rarer. This is particularly a challenge with rock recording roughly around the 80’s era. Once I hear really excellent dynamic recordings such as, for example, many of Jan Garbarek’s (ECM generally as well), Radiohead - King of Limbs, Trifonic - Emergence, just to name a few, I don’t soon forget them and I find myself returning to them like sirens as the years pass!

At least from what I’ve read day-to-day from Paul McGowan regarding designing, and then listening, seemed to apply most to the speakers they are creating where they use the IRS Vs as their archetype sound to try to match and then build upon without simply copying Arnie Nudell’s incredible speakers (not just add modern crossovers, etc). They found that two different speakers prototypes they came up that demonstrated the same “math” on “paper” sounded distinctly different. They also found that creating a world class speaker is extremely difficult. I get the impression it is arguably the most difficult component to “master” from the ground up even when you know your specific goals. That really stuck with me. Anyway, that’s a whole new rabbit hole discussion. 
@hilde45 my compliments on your moderating. Want to do this for every top level discussion on Audiogon? You’re the antithesis of our loathed friend, who shall not be named, that thankfully got banned a few months ago. He “thought”, for instance, the best, and only speakers worth anything, would be a concrete edifice that he would somehow design with his all encompassing wisdom 😂. All he did was unleash anarchy and anger, accompanied by virtual torches and dynamite, into the population🤬🔥🧨.