Nope. I've never had any trouble hearing differences in amps. In fact, to
my
surprise, I just replaced two Zapco amps the other day with a single multi
channel Xtant and the Xtant actually had a much cleaner high end with a
bit
more air. I could hear drumsticks hitting the cymbals just a tad clearer,
and I could hear fingertips on the guitar strings a little better.

Yeah, and I'm sure you performed all the necessary controls. Could it be
perhaps that the new amps were more powerful? Did you conduct a proper
blind test?

Besides, just the difference in power supplies alone would make the
Zapco/Xtant/JL/PPI amp sound tighter and cleaner. Anyone who has any sort
of
electronics training will agree.

How?? You've yet to tell me how, even though I've asked you repeatedly.
Why do you keep avoiding the issue? Please, be as technical as you'd like.
My degree in EE and my experience designing and building amplifiers will
allow me to keep up with you.