differences between tube and solid state designs

I know what you mean about high end... it took me a while to see how tubes also, to my mind, handle the low end better. The hard clipping of solid state can really take you out of the music, the movie, whatever. Soft clipping, and a certain "trueness" in the staging of the bass, aka holography in creating a tone to the room the music is in, I think it has to do with sympathetic chord reproduction, is what I appreciate as much now.

Differences in KT88 vs the KT90.
Anyone wanna take a shot.
I much prefer the 90 over the 88. There is nothing about the 88 tube I like. I like everything about the 90. btw notice how few amps offer the 90.

"I suspect that some of the low-level articulation advantages attributed to high efficiency speakers is due to their typically being driven by Class A amplifiers which have no crossover distortion]."

The sensitivity/efficiency measurement of speakers is an expression of output sound level for a given input voltage. I am betting that the reason high efficiency speakers "articulate" better at lower levels is that the volume is actually louder at the same dial setting that you used for the less efficent speaker. Unless you have guaranteed that the sound pressure in the room is exactly the same for both tests, it's hard for me to swallow that crossover distortion in a modern class AB amp is to blame.

"Single-ended and OTL tube amps do not suffer from this effect, known as hysteresis."

All magnets suffer hysteresis losses. This includes transformers. OTL amplifiers parallel a bunch of tubes to get the output impedance low enough that a transformer is not required, but every single ended tube power amp I have ever seen has one.

And you determined these amps that you were listening to were clipping how, exactly? I constantly hear this stuff on these groups, hard vs soft clipping, even vs odd harmonics, class A vs class AB, tubes are valves and transisters are switches, etc.

You want to know why tube amps sound different than SS amps? All you have to do is look at the frequency response graphs published in every Stereophile review and look at the trace using the simulated speaker load. The amplifier's output impedance is basically in series with the speaker load. A tube amp's impedance is so high that it creates a divider network consisting of itself and the speaker load.

Tubes - Big humps at 65-70 HZ and 1.5 KHZ, big dips in the mid bass and treble, dropping sharply after 10 KHZ.

SS - Flat.

"SS - Flat"

Couldn't have said it better myself. I've always found SS amps to sound flat.

Sorry, couldn't resist. :-)