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

@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.

I have only owned two tubed components.  One was a Prima Luna integrated amp, and I hated it and returned it.  It sonically was the equivalent of pouring maple syrup over a steak.

  However, my favorite preamp for the past several years is Cary Audio SLP3.  This broadened the sound stage and fully fleshed out instrumental colors with sweetening everything 

"Tubular" Dudes

The surfers nailed it years ago