What determines good distortion?

For me, distortion is distortion. It is never good. Some are just less offensive than others. SOme might even sound pleasant. But look up the definition of distortion.

If your goal is to reproduce the original as accurately as possible, it is NEVER good.

If your goal is to make the original better in some way that you desire (although concurrently less accurate), then some distortions might accomplish that. Distortions resulting from soft clipping versus hard clipping is a common and valid audio example.

Note that soft clipping is more common but not unique to tube amps and hard clipping more with SS amps, but some SS amps may also soft clip though I am not sure if any tube amps hard clip?

Better to be safe and avoid clipping altogether by not skimping on the power needs of your speakers in your room. Effects of clipping can be subtle and not easily recognized way before the point comes where you can clearly hear it! THis is a very common scenario that affects many unknowing listeners out there who cannot understand why their system does not sound as good as it should.

I'm sure there are some things that could be done to even the Mona Lisa to make it more appealing to some, but that would result in a reproduction that is distorted in some way but for good reason perhaps. Would that be wrong?

Bombay,

I'm with you.

Distortion, whether good or bad, is determined in the head of the listener! So it's the listener who makes the only meaningful determination in the end.

Avoid clipping distortions though always! Oveer the long term at least, I doubt anyone with good hearing would prefer even subtly clipped sound using any amp technology to the alternative.

"This is why tubes are still around half a century after being declared obsolete. "

Atmasphere, I often wonder what the SOTA is in tubes themselves these days?

Are NOS tubes still the SOTA or has tube production technology advanced at all since the heyday of tubes in general 40+ years ago?

I've noticed prices of new tubes seem to be going up. Is that negatively impacting the value proposition?

"Additionally, it is easily demonstrated that even the most pedestrian tube amplifier will make less odd ordered harmonics than any transistor amplifier; a sine wave generator and an oscilloscope are all that's needed to demonstrate this."

OK, if it is so easy, can you demonstrate that please? WHich amps specifically would you select to do that?

ALso remember demonstrating something does not prove it. Other demonstrations with different amps could have different results.

Even if true, does that mean any tube amp is better than any SS amp? I doubt that!

I like tubes in general as much as the next guy, but just trying to keep things in perspective and avoid people jumping to conclusions based on partial facts.

YEs, I will chose to avoid clipping all together, thanks.

Easier to do with modern speakers these days with smaller and more efficient switching amp technology. These are game changers in the SS versus tube amp debate IMHO.

If my choice were limited to massive monster SS amp or tubes, I might chose the tubes as the lesser of two evils. Most likely I would go to high eff.speakers to avoid all the amp pain incurred with any large hot running, and heavy amp.

OF course some do not like the sound of switching amps they have heard either for whatever reason. Class A SS or bust! OR maybe tubes?

If you are going to clip, better off with a tube amp in general I would agree, though some SS amps claim soft clipping characteristics similar to tube amps though no the same.

I'm satisfied with the softening of the tube amp claim to accept that not all tube amps are inherently superior to any SS.

Tubes in the phono and line level devices is as far as I will go. What's involved to keep a tube power amp especially a large one running properly does not appeal to me personally, but may be the best solution for some.