How far have ss amps really come in the last twenty years?

I suspect that just like loudspeakers, when the amplifier designer engineers an amplifier to fit to a certain price point, he is also targeting an amplifier sound that he thinks best presents music as realistically as possible.  In other words, its not all about perfect square waves, SNR and THD.  Therefore, its reasonable to expect that different designers have different ideas of what sounds right...hence amplifier will sound different.

As Blindjim said....just try a few amps and it doesn't take long to see that either the amps themselves sound different....or the way they interact with the rest of the equipment results in a different sound.

Right now, I'm "trying out" a new amplifier called the 2Cherry from Digital Amplifier Company. Its class d, no modules, all in house designed circuitry using discrete components...and boy does it sound good...open, three dimensional, detailed, liquid...I could go on....for less than $3k....so I think there may well be room for continued amplifier development.

And in a way, I agree with Atmasphere...most of us say that we want as little distortion as possible...but I think we really want is what sounds the most like trumpets, pianos, guitars and voices that we have heard live...and maybe sometimes, to some listeners, a euphonic presentation is more pleasing.

Which component is further along? Speakers or Amps? Would the best speaker, cost no object, in the world show any shortcomings of the best, cost no object, amplifier in the world? Or vise versa? 

Alan Shaw would say there is very little new in amplifiers. Indeed, amplification technology is widely used and optimized for many purposes, not just audio, and is more or less a "solved" problem. For those of you who haven’t had the pleasure, this thread will show you some of his thinking. https://www.harbeth.co.uk/usergroup/forum/subjective-soundings-your-views-on-audio/electronics-sources-stands-cables-accessories/amplifier-discussion/2390-the-last-words-on-audio-amplifiers-jan-2015

And if you disagree, and can prove an audible difference under his conditions (gain matching), he's offering a pair of his top-of-the-line speakers (see the first few posts).  

And if you disagree, and can prove an audible difference under his conditions (gain matching), he's offering a pair of his top-of-the-line speakers (see the first few posts).  

That sounds nice. Might run short on speakers after a while...

Like shooting fish in a barrel. Do you have to fly to England to do the shootout?

I will take this challenge. It would be difficult for me, or anyone for that matter, to convince anyone else that differences are heard, unless they heard it too. If I were doing the amp comparison through my own system, in my own room, with my own selected music, I would, and have, each and every time, hear differences. Mr. Shaw seems to say, if the circuit is the same, distortions are kept at a minimum, impedances match, and the amps are working comfortably within their limits, the 10K amp, with all of it's better parts, more heavy duty chassis, larger power supply, etc., will not sound better, or even different. Wow, is all I can say, if I read, and interpreted correctly, all that I read. Does this mean Harbeth speakers use inexpensive crossover components, because Mr. Shaw hears no difference in better capacitors, etc ? As far as a system I am not familiar with ( different equipment, room, etc. ) ? As long as I am given enough time to listen and evaluate this system, using my own selected music, sign me up ! Enjoy ! MrD.