JA does deserve our thanks for attempting measurements and speculating on correlations with his reviewers' impressions. Perhaps someday I can persuade him to understand current noise and test accordingly, and find out how he came to suppose that the worst-case conditions for an amplifying device's noise occurs with a shorted input.
Is that a euphemism for "dances around when his reviewers can't pick up obvious defects?"
That said, he does a generally fine job with measurements. Your caveat is well-taken, and it would also be nice if he did the same kind of Power Cube measurements on power amps that Audio Critic used to do.
Agreed. I am talking about smart well educated people making mistakes of various kinds very frequently in their everyday lives. It's true that experts in given field are more likely to be correct in their intuitions related to their exact field of expertise, but not outside of it. You are obviously expert in E&M and related technical areas. But I don't know about other areas. Let me ask you a question you might know about: Do you think it would be possible to design a neural network or other AI system that could recognize low level but measurable distortion by learning from data?
Also, I would just like to mention that I don't claim to have extraordinary hearing. Everything I have ever noticed when listening to sound could be heard by other people simply by asking them to try focusing attention to it, such as focusing on the sound of a cymbal in a particular frequency range, something no casual listener would probably bother with or think to do. So, when you refer to all the well established psycho-acoustic research out there, I would like to know more about how the research has been conducted. And it sounds like you would like the people who claim to hear more than you think they can to get out there prove it scientifically. I would like to see that too, as well as to review the existing work already done. But I am not going to make a career out of this at this point in my life. Not me. So, we maybe we will have to disagree a little for now. I am with you already on the more far-out claims. But, I don't find you as credible in the psycho-acoustic area as in E&M, and if we disagree it is probably on the psycho-acoustics side of things.
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Yes, I see that with engineering and faith-based audio types who are clueless or even aggressively ignorant about sensory testing. Like people who don't bother doing literature searches about decades and decades of amplifier testing.
Well John admits to being baffled at the absence of correlations, and even the negative correlations, between generally-acknowledged basic performance metrics and his subjective reviewer preferences. That one integrated amp (was it Croft) with hideous phono repsonse errors even led him to have two different reviewers listen---and both gushed on about how great the piece was.
In another case where I have more intimate knowledge, a subjective reviewer didn't detect the loss of at least an entire octave of high frequency response, something moreover readily concealed in tests where the Ap signal generator provided the input drive---i.e., not the appropriate series R-L source. In that case I don't think the phono preamp was easy to measure as it was captive to the overall product, so there were no Ap measurements at all.
Power cube measurements would be lovely. That was something that Harman Kardon used to do and even publish.
In another case where I have more intimate knowledge, a subjective reviewer didn't detect the loss of at least an entire octave of high frequency response, something moreover readily concealed in tests where the Ap signal generator provided the input drive---i.e., not the appropriate series R-L source. In that case I don't think the phono preamp was easy to measure as it was captive to the overall product, so there were no Ap measurements at all.
Power cube measurements would be lovely. That was something that Harman Kardon used to do and even publish.
It's not that mysterious when the hiring criteria for those positions have more to do with creative writing than ability to analytically listen.
Don't laugh, when I recorded a Lee Barber concert in my living room and played it back a couple days later, at one point my wife said something on the recording. My dog ran over to the speaker and started barking furiously. "OH NO, SHE'S TRAPPED IN THAT BIG BLACK BOX! COME SAVE HER!!!"
Quad indeed designed great gear and even the early amps were transparent.
When I moved to Japan in the early eighties, I brought a Quad II, a pair of Little Red Monitors, a pair of small KEF's, plus a couple of 15" Philips drivers in large enclosures from my student years. While there, I bought a Luxkit switchable A/AB amp that was sold only to Japanese geeks, and managed to put it together from just pictures. Later I bought a second one. Great amp with specs like only the Japanese managed at the time. These amps were in a different room from the speakers.
When I forgot which amp I had connected, I could not tell from the sound alone which of the three amps (the Luxkit because of A and AB counts for two) was playing! And this at a time when I was sincerely dissatisfied with the sound I had and was eagerly looking to improve it. My ears were really sharpened to find out what was wrong, hence also the Luxkit.
In the end it all came down to the speakers. Designed and build an active crossover to integrate some of the loudspeakers and amps I had and this was the real breakthrough. I have been running active systems for over 30 years now and am very disappointed that 'high end' still means trunks filled with coils and caps in speakers. The biggest and most obvious improvement that can be made to sound reproduction in the home is still largely neglected.
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First I've heard of him. I looked him up and I think it's time for a search at Amazon to buy a book or two of his.
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Unfortunately, I'm neither gaunt, nor well-dressed, nor elegant, nor a cigarette smoker.
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