The most important acoustical factor to test when assessing a system S.Q. is the basic essential one:
"Timbre tonal playing perceived surface and volume micro-structure" ... A piano note or a chord or a succession of chords for example appear like an islands archipelago on the sea of silence with his own complete internal and external shape and geography in a fleeting instant in the room...
You can have powerful dynamic, soundstage, imaging in any system relatively in some QUANTITY... With basic simple rule of installation and basic acoustic ...
But you cannot create very QUALITATIVELY good perceived TTPPM (timbre tonal playing perceived micro-structure)
Without using OPTIMALLY all the power of acoustic CONTROL in a dedicated room and vibrations control and method to decrease the electrical noise floor, and all that with the synergetic complementarity of the chosen gear...
But all that is useless if someone dont learn to use NON AMPLIFIED instrument and voice to explore with listening experiments and test controls...We are programmed in our short personal and million year evolutive history to perceive in ALL acoustic conditions the TTPPM of the human natural voice...
High frequencies, bass, mids characterisation are AUDIO general disjointed concepts about sound that are not the TTPPM...
Audio vocabulary cannot describe it....
It is a sound/music unifying perceived quality...
TTPPM is like a perceived human face.... Details here are not and are never only sounds like bordering EXTERNAL details like it is suggested in usual popular audio vocabulary... Details in TTPPM are flowing COLORED AND SHAPED and perceived intertwined internal EXPRESSIVE parts...
They are experience difficult to translate in words...
We learn to listen, nobody KNOW by innate election how to listen and what to listen...
Sound is to the internal perceived music in us what the external perceived body in the room is to the soul....A unity....
Because of what i said the music/sound experience is a JOURNEY different for each one of us... NO EARS ARE THE SAME AND NOT ONE HISTORY IS THE SAME....NOBODY is the master of other human being here, we must learn ALONE....Nothing will replace listening personal experiments....Any guru here is a seller willing it or not.... I respect much the honesty of the OP about that... It is the only reason i listen to him , his honesty, not for the components supposed S.Q. value at all ... I need his honesty in his journey not his components....I am more interested by him than by any piece of gear in fact he speak about....I dont buy gear, mine is enough for me anyway... Audio experience is related to exploring many piece of gear, but OPTIMAL S.Q. experience is related to ONE CHOSEN system by one pair of specific ears in a specific room....
By the way a dedicated OPTIMALLY small room is SHAPABLE FOR A PAIR OF SPECIFIC EARS with reflections control and time and timing control in a way a greater bigger room could not be.... Small room acoustic is not Hall acoustic.... This is very different in acoustic setting possibilities... The only true LUXURY in audio is owning a dedicated room, not the price of amplifiers or speakers...
Installing optimally a system can take months and years....It is not plugging a new device to upgrade, defeating and replacing in this way the necessary complex installation of the gear in the mechanical,electrical, and acoustical working dimensions of the system....
My motto is: embed everything rightfully before upgrading anything...
I know very little myself, what i learned i learned it myself in the last years with THE SAME GEAR in a continuous set of listening experiments....I am only a retired man listening music with a ridiculously low cost but relatively good system for me and my purse in a dedicated room .... This is only my experience and impressions...
I will not say much more....
I apologize for my rant....
Merry Christmast to all, especially to the passionate OP....