yeah, tubes in the front end
my music sources start with tubes in the arc sp3a1(C) and end in an adcom 555II for power. the video sources pass through the arc on the way to the amp.
the difference between the adcom preamp and the arc was nothing short of amazing. i strongly advise that tubes belong in the front end. a tubed amp would be interesting. the vincent 100wpc amp reviewed in tas ($1000) would be high on my list of candidates.