Just talking out loud, but I wonder how the top-end speakers of yesteryear would compare in an A-B audition.
@bdp24 -- I drove (or should I say, over drove) my 2000a speakers with a Crown DC 300 amp. Talk about an electronic IN-compatibility. I had to run the amp with the protect circuit in "off mode" because the amp thought it was shorting out. The high-end impedance was probably in the low single digits because of the electrostatic tweets. I also blew them out on a regular basis. I also recall that the inductors got so hot, I couldn't touch the mounting screw head that held the x-overboard down.
The 1001 and 2000a speakers touted a transmission line woofer set-up which used a cardboard tube stuffed with damping material. Frankly, it looked like a bass reflex system to me. FWIW, J. Gordon Holt rated the 2000a as Class B speakers in the day, which was pretty impressive. And yes, I remember when Stereophile was sans advertisement and paid subscription only.
Btw, do you remember Nel's custom made 10 foot high (or thereabouts) downward firing subwoofer tower? Nel cut the woofer off at 5 or 10 Hz because he was afraid that it could make 2 Hz sound energy that would boil a person's blood or something crazy like that. :)