Tube sound is not about warmth. It's about correct presentation.

My experience with tube amps has not been better than solid state. I've liked some tube amps well enough, but I have yet to hear what it is that gets others so excited about them. In any case, I'll agree with the OP's assertion that proper presentation is what I'd want from a tube amp, and I've heard some do it just fine. 

ghdprentice's description suggests that good tube amps sound plain and natural, not exciting or magical. Maybe that's what I failed to understand while listening to them. I've read so many glowing reports of some captivating, mesmerizing, transcendent effect that I expected to be wowed, when that's the opposite of what they do.

In this hobby anything opposing tubes in general and S.S. or digital and analog or turntables to dac, or music lovers versus audiophiles , is almost more annoying than informative ...😁

The reason is simple: the quality is more in the implemented design than in the parts choices and too many factors differentiate each customers journey, and needs , and ears, system coupling , room acoustic, psycho-acoustic biases , fetischism, and knowledge etc then imposing a choice once for all for all situation is preposterous ...😁

Psycho-acoustics and acoustics rule over gear, when synergy is reached ...And rightfull mechanical and electrical embeddings controls exceed many upgrades half of the time if not more in acoustic impact ...

These rules apply for most people with limited budget not for people with no limit for audio budget ... Then my rules apply for most people who must make CHOICES and who cannot afford 500,000 bucks system and acoustically professionnally designed room ...

For example the fact that on a very costly system a costly turntable can beat AT THE END a costly dac had no useful information for most of us and our more mundane low cost choices ... It is better to have a top dac in an optimized room than a top turntable in a living room ...Too much factors are at play , it is useless to claim anything superior once for all and for all needs ...

@mahgister +1

putting all tube amps in one basket and comparing it to single basket wit all SS designs is a little bit “incorrect sound equipment design development” representation! :-)

there are plenty of good sounding, warm (meaning linear) SS amps, incl x-fet, v-fet, darlington, class A, G etc on market. typically “warmer” sounding SS amps cost more, because devices used for output stage perform better (less distortion with less fb) at lover current, thus require more of them, matched/selected, in parallel.

warmer sounding tube amp is “easier” to build, if you have high quality matched tubes, expensive transformers, capacitors etc., which cost plenty. tube amps require more often maintenance, tube replacement, bias/bal adj. etc. 

for 25 W range amp I prefer tubes, for higher power and low freq. content music I prefer SS (accuphase A, ML).

@asctim “…good tube amps sound plain and natural, not exciting or magical.”

Let me change the gist of that a little. By being natural… and musical, they capture the magic of the music. I absolutely find good tube amps magical… they can send shivers down my back and goose bumps on my arms… it is the reality of the music, so exquisitely reproduced. Anyway… that is what I am talking about… nothing plain.

In other words, good tube amp just sounds right, the way it should be. And that's kind of magic, yes.