I disagree with this. If it takes upwards of 1% distortion of both even and odd order components to be audible, ain't no way I believe that odd order alone hundreds of times lower is going to be audible. I do believe that odd order is "worse" than even. But over a hundred times lower is still over a hundred times lower.

Fully balanced components have been around a while. They have been reviewed by many publications and many reviewers. If a fully balanced design is so detrimental to good sound quality, why haven't more reviewers commented on this with measurements to support it? I simply have not seen that. What I have seen, is an awful lot of people who do tend to prefer the sound quality of fully balanced components.

You seem pretty sure of this. Would you care to tell us about the double blind listening tests you've performed between balanced and unbalanced amplifiers to back up your position? (I'm not interested in what manufactruers or reviewers say - just the results of your own tests.)

After all, you didn't believe me about the fact that balanced designs cancel even order distortion, did you?

Actually, I have done 2 sighted tests in the last 12 months or so:

1)


At one time, I had Proceed (fully balanced with balanced connectors), Bryston (not balanced with balanced connectors), and Acurus (not balanced with just RCA jacks) amps all on hand at one time. I did extensinve listening tests over about 6 months. 2 channel music and movies. I ended up keeping the Proceeds. They just sounded smoother on top with more mid range detail and clarity, to me.

2) Drove 160 miles last summer to go listen to a Pass Labs X150.5. At the dealer, I also compared that amp to an Aragon 8008 Mk II. (The Pass Labs is fully balanced, the Aragon isn't.) I preferred the Pass Labs amp. This is the most musical sounding amplifier that I've ever heard.

Now, I personally don't think there are large differences between amps. I agonized over the decision to replace the Acurus amps, that in one form or another, I had had in my system for about 8 years with the Proceeds. The Proceeds cost a fair amount more, and even though I did prefer them, the differences were subtle at best. But to me, they were there. The point is, is that I had no ulterior motive to preferring the fully balanced design in this case, and in both comparisons, the fully balanced amp certainly did not sound *worse* than the single ended designs.

So there.

I said blind testing, not sighted testing. It is well documented that sighted testing is essentially useless in determining subtle differences.

When I was a test engineer at Altec Lansing, we performed literally hundereds of blind tests. During the design phase of one line of amplifiers, two amps were designed to be as identical as possible except that one was fully complementary (balanced) and one was conventional. The conventional amplifier sounded much better, and more like a tube reference amp than the balanced design. The balanced design was abandoned in favor of the conventional one.

Useless to you maybe.

From Jim Austin in the latest Stereophile.

Tell you what- you keep believing what you want to believe, and I'll go enjoy my system some more.

I hope you don't believe everything you read in Stereophile - the "audiophile community" is hardly the ultimate technical resource!

For those of us that don't quite understand the difference between odd and even order distortion and the difference it makes I have included a piece of an article that will help explain some of it.

As you probably know, harmonics (also called overtones) are what make up the timbre of
each instrument so that the A440 of a clarinet sounds different from the A440 of a
saxophone. The sax tone is rich in harmonics while the clarinet sound is almost pure
fundamental without overtones. Certain harmonics occur naturally in music -- both in the
overtones of timbre and as component notes in the harmony of chords. These overtones are
often called the "low order" or "even order" harmonics such as the 2nd, 3rd and 4th. These
overtones relate to the fundamental note by being one octave above (double the frequency);
an octave and a fifth above (called the "quint" in pipe organs, an octave and a half above)
and two octaves above for the 4th.

The ear has a great tolerance for these overtones - because they relate in a musically
consonant way and are are already present in the original signal, as either timbre overtones,
upper harmony or both. For example, it is often possible to add up to 20% second harmonic
to a single note before any change is audible. Then all that happens is that the ear hears the
timbre change.. it does not hear "distortion trash." If you're a guitar player or keyboardist try this simple experiment. Play two notes, play the low one loudly and the high one very soft at
first, then increasingly loud, an octave apart at the same time. Notice how loudly you can
play the upper octave note before you can even hear it... and that what you do eventually
hear sounds mainly like a timbre change in the lower note -- not two separate notes. Now try
playing the same original note but this time also play a note two octaves plus one step
above. No matter how softly you play this note, it is distinctly audible and separate from the
original.

What we've done with this experiment is demonstrate the effects of different harmonics in
contrasting distortion types. You've heard how inoffensive the low order (sometimes called
"even order") harmonics can be... especially compared to the prominence of the upper order
(often called "odd order"). And as you might guess by now, tube amp distortion is primarily
low order while that of most transistor units is odd-higher order... and hence very
objectionable. Clearly then, a tube power amp with a higher percentage of Total Harmonic
Distortion actually can sound cleaner and clearer and much less harsh than a solid state
amp which carries a lower total distortion rating. It's not the total distortion that counts as much as the distribution of distortion components: It's all but impossible to hear even a few percent of 2nd harmonic distortion whereas a fraction of "high order" type becomes audible
as annoying hash.