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

 @atmasphere  Distortion is an interesting term. Distortion compared to what? You mention that the human ear treats 2nd and 3rd harmonic distortion favorably. Therefore, one needs to question whether these distortions are distortions at all. Since we, as humans are using our ear/brain to determine what is considered as a true  and pure signal, wouldn’t it make more sense to label a signal that doesn’t include these 2nd and 3rd harmonics as the signal that is actually distorted...?

@stringreen, I would closely watch the temperature of your amp for overheating after the heatsinks were taped up. To function properly, they need to have maximum surface area exposed to air, and to allow air to move by convection through them. 

Thanks  for your caution....  In fact, the amp only gets warm - never hot to the touch.  ...and too, the tape was put on by the factory.  It covers only about 15% or so of the fins, and only in the horizontal plane...the fins are vertical.  Thanks again - I'll be vigilant.

I've spent 50 years or so as a professional musician in different bands, although in recent years I'm far more likely to gig playing solo acoustic (still play electric often), and to say "You stated you were in a band, so I believe your ears are shot" is ridiculous. Are the great long-term working recording mastering technicians in that boat? Ear issues will arise more likely with some musicians, but not all, and the ability to have excellent taste and an ear for what's right that develops over years of experience is something I cash in on often as a live sound mixer/technician, even though some tinnitus and inability to hear a dog whistle may be limiting somewhere. Also note that inna is here to win...hmmm....I think all well designed amps SHOULD sound somewhat similar as they're supposed to be replicating whatever goes into them as accurately as possible, with the subjective tastes of the listener finding what minor tone and coherency schemes fit them best...for me it involves tubes since they seem to get at the life in instruments more readily, or an early wind up gramophone could be great for lower arm exercise which has zero to do with this topic but I tossed it in anyway.

as for the insight on amps have reached their zenith, and or are all alike now, well, that is pure nonsense.

neither are they indistinguishably similar in build, they are different sonically as well.

just my input, mind you, but I trust my ears and hear distinct diffs from many amps and preamps when both are of the same brand or house sound, or as separates which has been my usual path for building a system.

naturally the only true way to ensure or prove positive once and for all, would be to have several amp makers gear set onto the same brand rack with the same source device and roll them into a room with a pair of speakers which have been optimized for that room and play them all one after the other off a set playlist.

this scenario ain’t ever gonna happen.

another way to get the evidence all amps are not equal is to buy some and listen for yourself.

this I have done along with so many, many others and found out as said, amps are NOT all alike or even too close to call sonically, not even SS amps regardless their classifications.

its ridiculous to believe they are!

of course for those who actually do believe amps are more alike than not, it is sure gonna be a cheaper and shorter path to their audio Nirvana.

they could simply buy a Bose setup and be done.

on this topic….
to get deeper insight or just some texture, on amplifier innovation, design, and concepts this link reveals an article which addresses major amp icons thru the years and those people responsible for them.

https://www.theabsolutesound.com/articles/the-12-most-significant-power-amplifiers-of-all-time/

I found the most interesting part the time frames for these designs many which date well back into the 20th century, and how ground breaking many of these products have stood the test of popularity and time together, remaining viable and often sought after products even in today’s market.

until we see plasma conduits carrying anti matter fueled power supplies, or photonic signal converters or the like amps aren’t going to see much of a complete face lift in the near future.

what role will amps play when the sOTA finally arrives at life size Hallograms in the home?

someone is gonna have to figure out how to get point source audio info from every axis within that setting to coincide with the visibly displayed content… and I think we’re back to converting electrical signals into and back from photonic means.

the curren optical fiber conduit merely carries a signal, it does not develop or manipulate it what so ever, it is just another kind of wire or pipe information passes thru and nothing more.

to accomplish it, will take a new kind of ‘wheel’..