Tubes Versus Solid-State Audio Amps—The Last Word

I just ran across an interesting 2-part article published in Electronic Design Magazine (one of engineers subscribes to it). I'm not saying that I agree or disagree with the author's conclusions. But I think that it's a good primer into the mysterious and opinionated world of audio amplifier design.

Why do Tube Amps and Solid-State Amps Sound Different? Part 1
Why do Tube Amps and Solid-State Amps Sound Different? Part 2

Warning: it's a long read and it's technical. The best summary is an excerpt from a response posted by the author:

"The startling realization was that when we took the same type of push pull amplifier used in a basic tube amplifier and replaced the tubes with properly biased and padded solid state devices, the sound was very comparable, which leads us to believe that there's more at play than just the stuff happening in the pn junctions of the solid state devices VS the stuff happening in the vacuum space in the thermionic devices."
A nice try, but way too simplistic. Esp the handling of passive components like resistors and caps. No one has used MLCC caps or carbon composition resistors in analog audio since the 70's.
If the final conclusion of the article is true there would be no difference in sound due to tube rolling.
Therefore, my conclusion to these articles is - if you can't dazzle them with the wisdom puzzle them with b...s...
Very revealing conclusion regarding "properly biased and padded solid state devices". What do you hear when your tube amp's bias is off? I've never heard shrill or harsh sound coming from a properly biased quality ss amp. The exact reading fluctuates on a "bell" curve on a wide margin whereas the "sonic" apex is a sharp point. This is why there is such a broad and varied point of view about ss amps. Accurate adjustment is haphazard and incidentally hit or miss at best due to pure ignorance or indifference. The notion that 10% either way is not sonically noticeable is hogwash. The closer you get to the "sweet spot" the greater the difference sonically. The further away you get, the less noticeable the difference with the added bonus of absolutely no stereo image peppered with all the undesirable traits attributed to ss. When truly accurate adjustment is approached, there is a tremendous sonic change that occurs. Having exact readings does not necessarily ensure a proper adjustment. It could still be, and probably is, way off the mark even though readings on both channels is identical! Once you're in the ball park, you "must" fine tune while listening. There is no other way. Yes there is a certain similarity among ss amps and it's all a notch above tubes if and when given an equal playing field.