Depends on your system (speakers) and the type of sound you desire. But, I can tell you that there are some pretty darn good tube and solid state pre-amps out there, so simply stating that a tube pre-amp is best is, well, not quite accurate. same for saying that a solid state amp is best coupled to a tube pre-amp. Borrow a few tube and solid state pre-amps and amps that you would be interested in, connect them to your system in your home and listen for yourself. My system currently has a tubed pre-amp, Audio Research REF 3 (would like a REF 5SE, but that isn't happening any time soon), coupled to two Mark Levinson 23.5 amps, driving Martin Logan Monolith III speakers with a Krell KSB balanced electronic crossover configured for my speakers and I am very happy. I have heard the new Audio Research REF 250 tube amps and if I could afford them I would get them immediately. They are on a very short list of the very best amps I have heard. Tube or solid state. And the REF 5 SE is one of the best pre-amps I have heard. So, depending on the sound of the setup, I could go either way. In my system, with the REF 3 driving the crossover and then subsequently driving the two 23.5 amps, this is as close as I'm getting to "there" without spending a ton more money, and contrary to what some may say, the 23.5s are still one of the best amps out there.
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