Great stuff here many of which I can relate to. I've had many different revelatory moments listening to music along way. The initial one was hearing what good, tight & defined bass can sound like on stacked large Advents in too small a room that I covered all the walls w/ thick Karastan carpet samples I got from a friend to absorb unwanted reflective sound. My friends & family thought I was nuts but I loved it!
Next was building first one & then a second Hafler DH - 200 power amp to power the Advents which was great but then I heard ProAC EBS speakers & understood what midrange & high end detail was about.
I heard & bought a Conrad Johnson Premier 4 power amp w/ EL 34 tubes & along w/ a Jadis preamp & heard real depth & imaging for the first time which was a game changer along w/ my ProAc's . I've been hooked on tubes ever since.
Very recently I heard how great a quality, modern horn speaker can sound w/ tubes & bought a pair of Volti Audio Rivals. "Live" music sound as opposed to accurate "hifi".
For those of us who still listen loudly to rock, blues or jazz, tubes & horns are awesome!