I love Triode's AND Jim_swantko's comments. I've tried both, having had several different SET amps in my systems the last maybe-10 years, driving hi-efficiency (more than 100dB) linearrays. As the rest of my system increased in resolution, so I wanted higher-rez speakers. I quickly determined that I had neither the skills not determination to build them myself, and bought a pair of Audio Physic Avanti IIIs which were fairly quickly succeeded by the best speakers systems I've EVER hear, Vandersteen 5As.
I tried biamping them with a few different combinations of small amps but finally bought a pair of McCormack DNA-750s. WOW did my system 'come to life'. Altho I do not listen at high levels, these HIGH-power amps brought a sense of ease...effortlessness...that my system never had. Tccaux, I suggest you read Peter Moncrieff's review of the DNA-500...
http://www.iar-80.com/page5.html
...to get some sense of the McCormack sounds and then understand that the '750 is a further refinement (by the manufacturer, conrad-johnson) of the 2 significant principles Steve McCormack used--Distributed Node Amplification (meaning placing significant powersupply capacitance immediately adjacent to the output transistor) and fully push-pull, differential amplification (meaning that half the amp is pushing while the other half is pulling), and then buy a pair. I'm confident you will NOT be disappointed.
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