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

I really never cared about what topology was in use,
but I Do want reproduced music to sound like the
recording that is delivered to the music buyer.

Basically, push/pull is a processor in that it
possesses Common-Mode (any voltage that is common to
both sides of a differential circuit) Rejection,
called CMR by engineers.

Differential circuits and balanced connections are
used by studio engineers to overcome the Common Mode
distortions that are in building wiring, etc., by
cancelling them out to some extent.

It is just common sense that this same circuitry
will also cancel-out any form of musical expression
that also occurs in the Common Mode.

So, with differential circuitry and balanced connections,
you are PROCESSING the signal-- Push/pull is a PROCESSOR.

This kind of processing is in wide use in recording
studios for one reason only-- it's quieter. Signal-to-noise
ratio is higher.

The severe disadvantage of processing musical expression
in order to obtain high S/N exacts a price: a LOT of the
music is attenuated because the differential circuitry and
balanced connections cannot determine whether the artifact
should be processed-out, or not. Any music signal/s that
is/are in the Common-Mode WILL be attenuated, period.

This process is NOT linear musically. It only MEASURES
linear in the portion of signal that remains, and this
is NOT the entire signal.

THE BEST recording labs are 100% Single-Ended. This isn't
practical on a commercial scale, so is only done by small,
extremely high-performance recording studios where noise
can be avoided in-house by using special high-quality
wiring, and very short wiring together with ultra-quiet
in-house power..

The reason S.E. can sound better is because the signal
isn't CMR processed. It's that simple-- it's Direct, not
processed, so it sounds more true-to-life.

In any Class A amplifier, both sides of signal are amplified-- a tube
or solid-state device can't conduct without both sides! (current flows when there is present both a PLUS and a MINUS).

The problem with push/pull is that the 100% complete signal
is divided into two halves in an amplifier. The signal reverses
every 1/2 cycle, so when the two halves are re-combined by
the circuit back into one-- the switching caused by signal
reversal (in any device) has had each side switched AND processed.

This cannot be linear musically, but people measure it so because
they are measuring the processed signal, not an original Single-Ended signal.

A Single-Ended signal is 100% complete. There are two connections
to make any circuit conduct. There are no "halves" in S.E. operation,
only the complete signal, with it's own internal reversals-- it isn't being FORCED into signal splitting..

The re-combined differentially balanced signal is also "complete" after
re-assembly by the circuit.

The only problem is that some musical artifacts have been processed-out.

People could, but they don't measure MUSICAL linearity.


Edits: 03/21/17 03/21/17 03/21/17

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