There must be many... I heard a pair of KR enterprise 6000 (I think) drive the 3,6 well -- but at a cost. Surely, big Jadis, Lamm & the like would do. Again, very expensive! I like tubes, but also find the 3,6 a difficult load at times (a good friend has these and we have experimented around: he also wanted tubes) and perhaps sticking to ss is a solution for now...
Cheers
Cheers