I've always been struck by (relatively speaking) how bassy his tone is, VERY solid and full. Along those lines, the 212 combos are closed back and ported. Hmmmmm . . . . . .
I remember Hartley Peavey talking about how fickle some of his endorsers could be. But . . . Ed was different.
When they were finalizing the spec for the 5150 cabs when Ed was partnering with Peavey in those days, he had ideas for different joinery and kinds of plywood for the 412's. So Peavey prototyped six different cabinets that were the same blueprint but with those differences, and Ed walked in, A/B'd all six and told them which was which, and he got all six right ! Hartley and the assembled crew were dumbstruck.
Eccentric, for people like that, somehow never seems to be the right word, but I've yet to get the right one, though gifted is close.
Joey