WHAT WAS THE BEST SYSTEM YOU EVER HEARD AND WHY WAS IT?

At Audio Alternative in Ft. Collins, CO.  You can google the name and click on the site to see both his show room and private set up. His set up includes Vandersteen7 mkii, Vandersteen subs, main amps and other equipment I am not sure of.  Listening chairs are very comfortable leather about ten feet from the speakers.  He plays only vinyl, mostly jazz.
Get ready!  The system no longer is a source of sound, but the room becomes a musical atmosphere and the sonic performance is as natural as breathing.  All in all, an incredible
experience and needless to say, very! addictive. 
I am not affiliated with Rick or Audio Alternative except as a happy customer.

It is not the most expensive that is the more impressive, the Elac combo Debut, heard in Montreal audio show, was unbeleivable for his price.

Boulder Amplifiers a few years back at an International show in Tokyo; a million dollar ( retail price ) setup playing vinyl.  I think this was the debut of their exceptional Phono stage... the Show was very well attended and the style as an audience member was to queue and wait to enter the listening room; the door would be closed, a track or 2 would be played and then everyone would be shuffled out.  I queued twice. Sound is often described in textbooks as "Waves" and the sensation of listening to this extraordinary setup was like standing waist-deep in a perfect surf where the Bass gently buffeted you, the high notes like perfect foam bubbles at the top of pristine waves... it was Simply Gorgeous and I have not before, or since, experienced such a wonderful system Now, if I had a lazy million....

When I referred to really hearing high end greatly matched systems. Some people just don’t understand what’s possible in Audio 

Fun topic...two outstanding systems stand out in my mind as they both incorporated speakers that at audio shows and retail establishments that I always found to be overly "bright" and not very appealing regardless of their reputations.  In both cases they were in high end audio shops that took the time to really dial them in and the results were absolutely amazing.  First was B&W 802D2's when they first came out, driven by McIntosh MC-501 monoblocks, C2500 pre and MCD500 CD player and medium level cabling, I think even Tributaries.  So rich and textured with a 3D / holographic presentation that was mind boggling!  It was like sitting in the middle of the soundstage with a height I have never heard again.  Not bright at all.  Second was with Wilson Sahsa's driven by Berkeley Audio gear with high end Synergistic Research cabling and room treatments....crazy 3D / holographic with tons of air and detail but no harshness or glare...just gorgeous!