The Absolute Sound vs Pleasing Sound

"...unamplified acoustic performances remain the standard for judging how close our systems get to the sound of live. As I’m sure you know that was the basis for the term “the absolute sound”..."

Indeed I do but that is about .01% of the type of music I listen to, so why use that as a standard? 

Frog, how are you ?
We always have an unamplified instrument with us - voice. If system doesn't reproduce voice reasonably well it is no good.
Record your voice on tape and play it. Next step play an acoustic guitar, just strike a few accords, record it and play.
If you only listen to amplified and 'synthetic' music, that's easier, though still it is hard to get dynamics right in a small room, and almost any room is small.

Cool. 

Listening is a simple thing that I know how to make complex - I can switch from listening to remembering and then thinking. 
And whatever works for you - do it. 

Amplified live music is very colored in itself.  The 'sound guy' helps create the sound, and some equipment and people do a better job than others. 

That being said, acoustic live, no amplification, is my gold standard.  From voice to violin!

frogman,

Of course, the ideal would be comparing live performance of non-amplified music with whatever we have at home. I was mentioning rock'n'roll because it seems to me that most of the members here (Audiogon, not necessarily only this thread) lean towards electrified performances.

At some point, I recorded a piano. As simple as simple gets, no fancy recording equipment, technique, or conditions. Portable MiniDisc with a microphone (around $70-100, I forgot details) in the room. It was surprising how close that recording actually came to the live piano on a relatively, for Audiogon, modest system. Maybe the secret was that both were in the same room, much smaller than any venue one usually listens to piano at. Our regular recordings are, as millercarbon pointed out, processed to resemble what many people along the way wanted them to resemble. Not always the faithful recreation of the event. Recordings bear some room imprint and attempting to recreate that in a living room may make things more complicated.