Excellent article in Stereophile

This is one of the most interesting articles I've read on harmonic distortion and its affect on sound quality and why the classic THD is a worthless specification. 

This is actually an old article that was republished, but worth a read nonetheless.
It is worth reading for research sources, but I find the article itself riddled with opportunities for more questions, and honestly, self promoting.

I'm definitely going to have to go back to those footnotes though.
I have and cherish and yes full disclose sold them eons ago one of the first SS amps to take advantage to Dr. Otolla research into TIM, the venerable Audionics CC2
....we also had Other brands chasing vanishingly low THD and they hurled in comparison 
It looks like much of what Ralph-Atma Sphere, has said is true.
Odd ordered harmonics, when reduced relative to the even, make for a more listenable amp.
Ben makes some pretty serious claims in this article, he claims to have figured out what makes Class A amps sound great, and an inexpensive way to replicate it.

I have never heard of any of the technology he discusses. It's 27 years later.

Anyone have examples to modern gear which might have benefited?
I'm genuinely asking, did his ideas succeed?
As an aside, he is right about fully regulated amps being desirable, and yet unobtainable. In recent memory the closest I've seen were a line from Krell and the Sander's Magtech amps, which are quasi regulated.

He claims to have solved the amp regulation problem. Anyone seen it?
why the classic THD is a worthless specification
Why pick on THD?

This thread https://www.diyaudio.com/forums/power-supplies/143539-look-lm317-lm337-regulators.html on regulator impedance is very interesting before it devolves.

Mr. Bau graciously modified the P.S. in my Rotel RCD-02 for Linear Z. The improvement is nothing less than astounding. As close to studio playback as I've ever heard.

There’s a lot hi-falutin’ gear out there with 10¢ power supplies...
This article is very old, and only one of many saying pretty much the same thing, that us humans are a whole lot more sensitive to some distortions than others.

Now there’s a reason I said "some distortions" and not odd-order harmonics, which is the one mentioned in the article. That’s deliberate. Because there’s a whole long list of things we can measure that turn out to not matter nearly as much as some people seem to think. Some people just love to jump to the conclusion that since we can measure something it matters.

And I know exercise is supposed to be good and all, but jumping to unwarranted conclusions? High-rez is better! Dynamic range! S/N! EQ! On and on. But if those all matter so much then how come people with no axe to grind or skin in the game prefer the stuff that measures bad, over and over again? Because I have yet to find the NON-audiophile who, given the chance to hear for themselves, prefers anything that measures better. Does. Not. Happen.

There was for example another article in Stereophile around this same time, reporting on an experiment that used random non-audiophile people listening triple blind to music played on systems that were 1. all analog/tube, 2. analog/SS, and 3. digital/SS. They went to such great lengths the girl handing them the questions didn’t even know what was going on, and handed them over from behind so even the expression on her face couldn’t influence them. Unsurprisingly, the clear preference of these normal people was analog/tube, followed by analog/SS, with digital/SS a distant third. The girl at the end said she knew nothing but wondered WTF was going on because she came to DREAD the sound of that last digital/SS system!

The sound that no doubt measured best. Of that I have no doubt.

So what’s interesting to me is not that people hear things differently than microphones, oscilloscopes, and other instruments. Hearing is an experience. Listening is an activity. Not mere physical phenomena like how rapidly the density of air or an electric current fluctuates.

No. What’s interesting to me is why so many so-called audiophiles still obsess over measurements that have been so utterly discredited over and over again for so long now?
@millercarbon - I was not aware of the Stereophile test you mention. Could you tell us the name of the article and whether or not it is available on their website? If you can provide a link that would be great.

It would be a wonderful irony if Stereophile touted the results of a blind test that determined that listeners preferred analog and tubes over digital and solid state. Stereophile has dissed blind testing several times in their publication and has taken a strong editorial position that blind testing of audio equipment is essentially meaningless.

The other thing about this test is that the difference in sound quality could be totally explained by the selection of the individual components. Did they compare top-of-the-line Audio Research gear against a Pioneer receiver? Did they compare a $10,000 turntable/cartridge with a $199 CD player? Was all equipment rated Stereophile Class A? Was the CD a good competent transfer of the master tape? During that time period Stereophile rated several solid state as well as tube components Class A. I've subscribed to Stereophile for decades and I don't remember this test or them taking an editorial position favoring one design philosophy over another. Their individual writers can have strong positions, i.e. Michael Fremer, but the magazine's editorial stance seems to be agnostic. If the results were that conclusive I'm surprised that they didn't refer to this test repeatedly. I would think Fremer would jump all over this test the but maybe he has and I just missed it.

Also, if the test was conducted in the early 90's you won't get much argument from me that the digital signal chain (A/D converters and D/A converters) were not up to the sonic standards of the best turntables and cartridges. Digital today is much better than it was 25 years ago and it would be interesting to see a double blind test that compares current state of the art digital to state of the art analog.
No idea, but it was long ago. Back when I subscribed, which I quit around 1994 or so.
The story, as I recall, it was not Stereophile it was just published there. It was NOT a test like you're thinking, asking a bunch of audiophiles which system they like better. Nothing so crude as that. Very clever, they asked questions more along the lines of which music did you like, would you like to hear more of it, consider buying, etc. So the subjects if anything would were focused on the music and NOT the system. They had no idea. They couldn't even see anything. Even the girl with the questions, who came from behind. They saw here arm, nothing more. Double-blind? HA! Quadruple blind!

Double blind is of course a canard. Red herring. Waste of time. Distraction. Refuge of scoundrels, etc etc. If you hear it you hear it. If you think anyone needs anything more, go read the previous sentences a few more times.

Ditto the state of digital. Replace double blind with the state of digital, previous sentences stand. One hundred percent. Because you could say the same about all the analog gear that was used. Its all a lot better today. Across the board. So might as well quit dodging and face the music. Heh.

Especially since one of the little-appreciated tricks they played was to use tube gear and solid state. So it wasn't just digital/analog. And lo and behold, the results placed the analog/SS below all analog and above digital/SS. Just like happens with everyone I've ever seen.

Everyone, that is, who is no audiophile. Only the audiophiles, they are the only ones who ever even think to say crazy stuff like I don't believe my own ears or what I heard might be in my head or gosh if only I were double blind instead of merely solo blind.

What a crock. Do you hear it? Or do you not hear it? If you do then why do you need your own experience validated by anyone else? So I can only conclude you cannot hear.

See how it works?
Not being an electronics engineer I often have no idea what he is talking about. He is not very good at describing things to lay people.
I would never pay for his time. Judging by the way he keeps his bench he spends most of it looking for things. 
I stopped reading specs around 1969 or so after I built a Dyna Stereo 120. An upgrade from the stereo 70? Lesson learned. I have always gravitated towards class A amps since I owned a pair of Krell KMA 100's
I have no idea if it is because of what he is talking about. But, on this one I will agree with millercarbon. The only devices you should trust are your own ears. 

Not being an electronics engineer I often have no idea what he is talking about."

I commend, applaud, and congratulate you for your candor, honesty, and transparency in acknowledging you're limitations in answering, responding, and opining on the comments referenced hear and such willingness to acknowledge limitations should be more common ideally in this forum.
Alls I know is I'm way way happier now that I abandoned technical excellence in favor of stuff I enjoy listening to.
The sound that no doubt measured best. Of that I have no doubt.
I've been maintaining for some time that harmonic distortion should be measured according to a weighting system that assigns a low number to lower ordered spectra and a much higher number to higher ordered spectra, especially the 7th and beyond.

But the flip side of that would be a spec sheet that allowed you to know how the equipment sounds! The industry doesn't want **that** - yikes! We've had the ability to do this for some time, but no collective will.
think atmosphere nailed it. Most don't know about the weighting equation and only see the product or end result.

if a person takes the time to measure each multiple orders on the primary freq, and then finds a way to minimize those, and ignore the product (i.e. answer) then you are getting somewhere.

If you read some of the papers written by Norm Crowhurst back in the 50s, you can see some did not care for the approach.
but the FTC adopted that means as teh way to measure amps, and back in the day, all the mfgrs jumped on board, so the die was cast.