On the first Stereophile Test CD they have a track where JG Holt reads from a Stereophile and is recorded in mono by about 15 different microphones including Shures, AKGs, Neumans, Telefunkens, etc. It’s not hard to tell when the microphone changes.What you just said about mic is right but you miss the important point about what is the difference between natural non electrically amplified instrument and voices timbre recognition in the database set of our brain species...
So I would say that what you are doing is making your system sound most natural to you. It may not sound most natural to someone else who uses different minimalist acoustic recordings to determine natural.
Natural human voice listening is the better test for an audio system....unamplified piano is good...Because of the sum of all the subtle cues there is associated with them...
Electronic music is the worst choice to determine more objectively if a system is good or not in a comparison implicating many people...
We dont speak about OUR taste here we speak acoustic...
Anybody could prefer moog electronical music over opera singing for sure....Saying that is saying nothing....