Hi,
I own Nautilus 805s, and have found them to really work well with tubes. At first I had a CJ preamp and McCormack DNA.5, then went to "Rev A". This was good, but then went to a AudioPrism Debut (Now Red Rose Music $$$), incredible midrange, but bass was a bit weak (I should NEVER have sold this amp, just bought a sub-that would have been magic). Then I went to Audio Refinement Complete, great little solid state integrated, but left me wanting... I have settled on Rogue Audio Tempest for now, and I love it. 60 watts in Ultralinnear, 30 watts in Triode (switchable), remote controlled volume (I never knew how much I missed this from my "Sony days"), and great, authoritative sound. Bass in UL mode is awesome, in triode it is a bit lacking. The Tempest is highly adaptable,, having preamp outs, both active and passive, if you decide to use a different amp later (it can also be mated to a Rogue 88 for a Bi-amp setup, the 88 is the same amp as the amp section of the Tempest), and preamp level inputs, if you decide you want to use a different preamp. I paid $1400 for mine used, but I think there's a couple of them on the site now for less than that. I can heartily Recommend Rogue, they are great to deal with and stand behind their products. Sound is great, the amp is self biasing, meaning no tube problems to deal with (other than replacing tubes every 1-3 years).
Anyway, I found that my 805's really like the Rogue! good luck