I've never understood the tube amplifier crowd. I guess I'm not looking to have some low-order distortion mixed in with my audio signal, or have my frequency response altered in some way because the amp's output impedance is high relative to modern speaker loads. Then there's current limitations into low-impedance speakers, massive power consumption, heat generation... yuck. If you must spend that sort of money on amplifiers, and I understand the admiration of great engineering, I'd rather have a pair of Mark Levinson 33s.
Bob Carver has got to be one of the most innovative people in the industry, and I have a huge amount of respect for him, but his infatuation with tube amplifiers and their "transfer function" is something I can't identify with.