Solid state amp vs tube amps

All things being the same, they will sound the same.

In general, yes… very much. Solid state tend to be much quicker but very easily run out of power. The often have much less mid-range bloom and rhythm and pace… resulting a much less musical sound. In general tubed amps will sound much more powerful and natural. I had top of the line powerful solid state amps for decades. Once I got a tube amp, I will never go back to a solid state.

Yes.   Anyway a big difference in sound...hard to use "quality" as a measurement of a subjective essence such as sound. 

Everyone has their opinion, as you see above.  But the main difference is power.  SET tube amps are generally 10 wpc or less and require high sensitivity speakers. Those who dedicate to build thier system around them tend to be prejudiced in support of them.

Those with less sensitive speaker, most people, become dedicated solid state guys.  they have no choice, and they often rationalize and justify their position and become ss guys.  They tend to be less supportive of tube amps.

In between you have to push-pull amp guys who have moderate power, can use speakers a little less sensitive and try to pretend their push pull amp is as good as an SET.

My point is we all end up in camps supporting what we like and it is unusual to find someone who is agnostic in the tube/ss debate.

So it is really impossible to decide which one you are without listening, unless you want to just side with the one with the best writing style.

Jerry

... And yet I went out and bought a Melton, P/P, KT-88 tube amp and much prefer my 20+ year old Yamaha RX-Z9 in "Pure Direct" mode. The Yamaha is a very high current amp and really bring out the high end of the Heils with so much more detail and the bass is fuller and more distinct. And I am a stickler for detail.

Use a good set of phones or monitors and the differences are obvious. Volume levels were matched to within a couple tenths of a dB. The Yamaha has >30,000 hours and the Melton has about 60 hours on it. The speakers have undergone modification since the videos, but the differences are still very audible.

Anyway a big difference in sound...hard to use "quality" as a measurement of a subjective essence such as sound. 

+1.  They do sound different.  "Quality" may be a subjective term.