I heard a flute, drum set, acoustic guitar, bass, and a violin in an outdoor setting last summer. No reflections to muck things up. No amplifiers, no cables, no wires, no transistors. I was about 50 feet away.
Sounded like my Vandersteens.....Powered by McIntosh tubes.
To YOUR ears, another combination may give simular results.
Personally, I find concert halls to be a bit harsh and like mentioned above, there is poor localization of the instruments due to the "Bose Effect" of too many reflections.
Of course, if you LIKE that sound, buy Bose!!
Whatever sounds good to YOUR ears, man!!