There you will find repeatedly stated the only two specs worth consideration are speaker sensitivity and phono cartridge output.
How anyone can utter such foolishness and also be taken seriously by even the few on this forum is beyond reasonable comprehension. Using this logic Robert Harley’s book should have been reduced from 596 pages to a paragraph or two.
When I inquired with Keith Herron a few years ago about matching his wonderful VTSP-360 preamp with my existing amp the very first question he asked was about my amp’s input impedance. Why would Keith have been the slightest bit concerned about such a meaningless spec? He apparently knows far less than other posters on this forum.
And why is Kevin Hayes at VAC so obsessed with the performance of his output transformers, putting tons of effort into his current delivery specs and optimizing power delivery into higher and lower impedance speakers? How misguided he must be.
Why does John DeVore believe that the entire load the speaker presents to an amp matters more than speaker sensitivity? He must be confused as well. I really don’t know how these guys ever managed to be so successful while being focused on specs that don’t matter at all.