I am glad I replied early. There are four schools of thought.
1) tubes are transparent, since electrons have no idea how they got there. Any difference you hear is all sighted bias except for very intentionally bad designs (SS or tube).
@SIY
2) Tubes are able to mask high frequency harmonic distortion, so even with a flat FR, it will be able to mask differences. It is about avoiding the rising distortion at rising frequency. You can also design Class D amps to behave this way.
@atmasphere
3) Tubes are a form a EQ and what you are hearing is just the effect of load dependency. (Several in this thread)
4) Tubes can be a complex set of non-linearities that alter the frequency response of music through a combination of distortion, compressors, expanders, crosstalk, microphonics, etc. It is NOT a simple EQ otherwise you could use a graphic EQ or parametric EQ. Instead you need to use more sophisticated software like VST plugins, compressors, expanders, etc. Unless you subscribe to the idea that it is all sighted bias, the very nature of tube simulations through VSTs strongly indicates that there is a difference.
While it is perfectly valid to say that you should have a transparent solid state system and then added the “musicality” to taste using software VST tools since you can turn on and off the capabilities, that would be the same as buying 16 Fosi V3 amplifiers with no power management for your home theater. You could manually walk to each amp and turn it on. In contrast, maybe getting the Trinnov Amplitude 16 makes sense for the convenience.
If you subscribe to the idea that tubes do have a sound that is more than just a measured but inaudible effect, are thoughtful enough to understand that everyone doesn’t have the same preferences, THEN it is equally valid to say:
Instead of dealing with complex VST, compressors/exciters, it might just be a lot easier to buy a box that does it for you: a tube pre amp or amp.
The tube preamp might impart less deviation from transparency than a tube preamp, again ignoring SIY and looking at many commercially available products. Individuals preferring little bit of tubiness would go for a tube preamp and those preferring more might for a tube amplifier, and those wanting the most, would double up.
It doesn’t matter that it’s a fixed effect, because it in fact is a dynamic effect. I have shown this with my analysis of this 300B SET. You cannot reproduce this using a GEQ or PEQ. It’s a more complex.
Raphaelite CS30-MKII 300B integrated tube amplifier review: A New Performance Record This is a review and detailed measurements of Raphaelite CS30-MKK 300B single ended tube amplifier. It is available on eBay for $1449 + $310 shipping to California + tax. There are some better deals from...
www.audiosciencereview.com
As evidenced by many science oriented tube and vinyl listeners here, it may very well turn out that the coloration is neutral to preferred more often than not for some listeners.
As evidenced by many closets, attics, garages, and offices of members here — a lot of people have more than one listening setup.
You can still demand good measurements from tube gear, namely
1) excellent control of your 50/60Hz mains noise. No one believes that this is part of the tube magic.
2) low noise*
No one wants noise during idle passages of music. The value of noise in masking distortion is a different story.
3) Minimal crosstalk*
Maybe it’s helpful for headphones, but even tube aficionados like dual mono designs, so a stereo product should minimize cross talk as much as possible.
4) Reliability
Stories of exploding designs are true. You are dealing with much higher voltages in a tube amplifier. Don’t feel bad paying a lot for a McIntosh or Audio Research or Luxman product even though it may use the same tubes that everyone else is using. You rarely hear about McIntosh tube amps exploding or causing damage to downstream devices…
I subscribe to #4. Right now, I have in fact, sold all my tube gear and all my passive speakers. I have held on to some of my vintage tubes in good condition and if I win the lottery, no doubt that I will be buying some tube electronics.