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RE: What an astonishingly insightful (and iconoclastic) assessment of some formerly revered designs....

There's nothing wrong per se-- with any of the explanations
I've read here. In fact, I think this is an excellent
discussion, but there is more!

Common-Mode finds its way into every part and every
wire, and every application in audio that is operating near
any source of alternating current OR musical energy..

Differential circuitry and balanced connections reduce
Common-Mode, as you well know.

I do not disagree with the THEORY or APPLICATION of
differential circuits or balanced connections. Fine--
we can agree here, but that is only a tiny surface
discussion-- the whole picture is much more.....

What you're not addressing is the fact that splitting
a common-mode signal into two halves and then re-assembling
it is not perfect-- it cannot be.

I think we can all agree that differential circuitry
reduces (attenuates) all common-mode-- signals, distortions,
and the common-mode that is music.

In a differential system output, you don't just get 1/2
plus 1/2 to form ONE. Since no build or wiring is perfect,
and no device is perfect, there is also Common-Mode mixed
in with it. The common-mode always contains both distortions
and musical artifacts... There is NO way to tell which is
which-- music can and does do anything that distortion does.

While the sum of the two halves of a common-mode signal
that has been split into two halves does equal a Single-Ended
signal mathematically, it does not consist ONLY of a true
differential output. The output is mixed with what Common-Mode
and differential distortions are left after the Common-Mode
attenuation of the differential circuit has taken place. The
output has also attenuated musical artifacts that are found
in the common-mode.

Engineers measure some of these things as various distortions--
aberrations from the desired "perfect" output, which would be
devoid of all Common-Mode.

That never occurs in real world equipment, and it never
occurs in music, either..

Single-Ended operation is all Common-Mode. You can filter it,
but you can't process-out the Common-Mode because that is
your musical signals! NOTE the Plural here...

The advantage of S.E. operation thus becomes obvious:
there is no Common-Mode processing/reduction of the
constantly changing musical signal's Common-Mode content.

Some of that common-mode content is musical artifacts,
not distortion.

What could be simpler? The S.E. signal is not
differentially processed, so there is no way to suppress
the common-mode content of the signal that is musical
artifact..

-Dennis-

.




Edits: 03/22/17 03/22/17

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  • RE: What an astonishingly insightful (and iconoclastic) assessment of some formerly revered designs.... - tube wrangler 17:36:50 03/22/17 (0)

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