I should've said revealing instead of "bright". My mistake. I've only heard one pair of Quads and they certainly weren't bright or cold. I haven't heard that many systems, overall, and as it's happened, those that were significantly more revealing than mine sounded fatiguing to my ears, so it's just inexperience on my part.
I'm a huge fan of '72 era Dead but have a love/hate relationship with the Jerry and the boys (and girl). I can't stand out of tune singing or sloppy playing -- the "ragged but right" ethos is an oxymoron from my standpoint. But at their best -- when they were both inspired and tight, (particularly from '71 - '77), I love 'em.
"Europe '72" was the first live Dead album I heard and it's consistency spoiled me forever. No full show from that year that I've heard equals it, for me. Inevitably there are clunkers intermixed with jewels. A perfectionist by nature, I'm not the type to buy albums because I like a few tunes, so I find this hit-or-miss miss aspect frustrating. I turn to the cherry-picked "Europe '72 and "Steppin' Out -- England '72" anthologies when I'm in the mood for that '72 sound.
I saw them in "73, '74 and '77 but due to the "recreational enhancements" popular back then, don't actually remember much! ;o)