I find it interesting that almost everyone of the songs and artists mentioned above have also blown me away. Maybe the Jazz, blues, folk, classical (and in that order) route just has something special about it.
However if you want epiphony then it must be Joseph Taylor singing Brigg Fair, what he must have sounded like as a younger man I can't imagine. He should be in the collection of every 'folk' enthusiast in the world. (rant over)