JA publishes measurements of speaker performance with apparently good precision.

I am trying to recall if there have been any sets using different amplifiers or preamplifiers?

It would seem an obvious thing to do, but I don't recall any off the top of my head.

I'd be curious, everything else unchange and measured identically, what we might see?

Still, of course, also hoping for the same to be done with a new speaker and then again as it is broken in.