I had an original 700 which I used with a variety of acoustic suspension speakers, including stacked Advents. I eventually migrated to a set of Quad 57's and tube amps, but before I sold the Phase Linear, I did hook it up to the Quads, very briefly.
And, no I did not turn it up.
:)
At the time it came out, there were very few amps with this kind of power- the Crown DC-300, maybe a few others- not sure any of them would pass muster today.
If memory serves, the original PL 400 sounded better than the original 700, too.
And, lastly, the apocryphal story I heard about Carver was that he had the circuitry and power supply rigged up in a prototype that looked like, or was, a coffee can. (Remember when you bought ground coffee in big cans at the supermarket?) He allegedly brought this mess to the 'Mac' clinic- one of those manfacturer sponsored events at the local dealer where you could get your amp 'measured.' (Sort of like dyno-testing). He apparently made waves--- not sure this is true, though.
