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And here's my problem with what people with your view say

"I've owned very highend solidtstate audio components in the past. As good as they were and some were VERY, VERY good, they couldn't hold a candle to my current SET amp, at least not in terms of reproducing music realistically. There's just something that's more organic or more complete to the music an SET amp replicates, that I've never personally heard a solidstate amp replicate."

It's impossible to judge whether a single component in a sound system is more or less accurate subjectively. We can only judge the sound system in its totality. You never hear an amplifier alone, it's always combined with at least a signal source and a loudspeaker. And then you have to ask yourself what is the amplifier supposed to do. What should it do if it were to function perfectly. If the answer is to make the sound system sound most accurate as a whole, then what must it do to achieve that. If the answer is that it must in some way distort the electrical signal as well as amplify it to compensate for another type of distortion elsewhere, then you have chosen a device which may be best in one sound system but worst in another. You have no way to know what will happen when you connect it somewhere else. As a control elememt it's hit or miss. At the same time, you have usually sacrificed one important characteristic of an amplifier, it's ability to deliver a powerful signal, for another, it's qualitative advantages within its usually modest power capability. How do you know which SET in advance will sound the best if measurements don't correlate? Do you have to try every last one to find out? Is there no way to determine what makes one better than another or what makes them as a class better than other alternatives? Cheevers answers this with a blanket statement about the distribution of harmonics in harmonic distortion. But reading his thesis critically, IMO he didn't even come close to proving his point and he didn't show that his point was even relevant. By comparing very different amplifiers he didn't have any control restricting his evaluations to the one variable he claimed was the object of his arguement. And citing very old technical papers written when amplifier harmonic distortion was typically very high, 5% to 10% or more, he didn't show that those arguements he cited was applicable in a world where a typical figure of merit is hundredths, even thousandths or less of what it was then.

If one were to really go about testing this thesis and proving its merit, what would he have to do? First he would have to go about testing the audibility of the differences in harmonic distortion distribution in a variety of different amplifiers. Lets suppose he could, by testing say 20 or 30 amplifiers individually and adding controlled amounts of harmonic distortion and finding that those which correlated with his weighting scheme were in fact audibly different through a series of DBTs (note I said different, not better.) Then he would have to go about carefully performing a series of live versus recorded demos using the various amplifiers demonstrating that when connected to different loudspeakers, listeners consistantly judged the recording closer to the live performance with amplifiers having the lower T.A.D. characteristics. This would constitute strong supportive evidence IMO of both the validity and relevance of his thesis. He unfortuantely did none of this. You can try to read the paper yourself. It isn't necessary to understand all of it to get the gist of what he is saying or how he says it. I didn't understand all of it myself and am not in the least ashamed to admit it.


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