What is the best sound system you ever heard?

It would certainly help one in developing a good sounding system to be able to listen to other systems, whether they were better or worse. But especially if they were better, you know, to give one a target to aim for. Compared to what? Stovepiping has its drawbacks. Tennis players oft comment they improve their game by playing better players.

The one way up on Red Mountain Aspen CO, the one Dave Brubeck used for practice late 60s early 70s. All McIntosh everything. Some unknown monster midrange horn, time delay system, and concert grand piano of course. Also some kind of Joshua Light Show panels. I recall there was a big bunch of Ducati racing motorcycles in the garage.