High-end amplifier clarification?

Adcom and early Parasound amps I don't consider high end. A high-end amp will provide a spacious soundstage, float the airiest highs, deliver a full but sparkling midrange, and has excellent dynamics/bass without sounding boomy. It should do all this and still sound musically involving & refined. Given that & without an equally high-end preamp you will fall short of your goals.

Atmasphere, Weseixas answer is very vague plus his statement that an amplifier should have the ability to drive a 2 ohm load otherwise he considers it midfi, is misleading. But if you do some searching under his user name you will see that his statement reflects his frustration to find an amp that will drive ribbon speakers.

Wolf garcia, you are correct, Boulder amps are high-end. The Adcom 565 mono blocks also are heavy with very large power supplies but they do not sound high-end. Just a case in point.