Slight thread swerve:
Fiddle-dee-dee on the EVMs: I've got a barely used SRO 15 in its box from the mid-'70s, and I've wondered for a few years how I could put it to use. I imagine it's not anywhere near as robust a speaker as anything you can get these days. But it is heavy! No boat anchor comments! I did used to have it mounted in my old Ampeg B-15N (my first amp), but that amp was already too heavy.
Back in the early 1970's we used to buy SRO's from Massimino Music on the east side of Detroit. We used them for everything.