Re: Valuable 12AX7!


mwcpc7@...
 

In a message dated 06/15/2001 8:43:03 AM Eastern Daylight Time,
europachris@netscape.net writes:


Capacitors, wire, resistors, tubes, transformers, ALL of it makes a
difference beyond what one can measure with a scope or distortion meter. I
am a skeptic, but personally witnessed the differences between half a dozen
.
1uF/630V coupling caps in an amp. It is subtle, but there. Ditto for
tubes
and wire. Speaker cables have a lot more going on than just resistance per
foot. There are interactions between the wire strands, the insulation, the
braid geometry (if any). Inductance and capacitance come into play and how
that interacts with the output impedance of the amp.
I have never read about this in the electronics literature, but look up the
phenomenon of "superwaves" in the field of oceanography. In perfectly normal
weather, the random energy of the ocean wave trains can suddenly all add up
in phase generating a superwave that can engulf ships and islands without
warning.

In audio, with tens of thousands of waves per second, the same phenomenon can
occur. The input transducer (microphone or magnetic pickup) will filter this
out initially, but random phase shifts within the electronics can re-phase
the waves to produce instantaneous voltage or current amplitudes far above
the average at the input. How this sounds depends entirely on how the
electronics handles instantaneous overloads. Tube circuits and analog
magnetic recorders are much kinder to these transients than are solid state
or digital systems.

My theory is that a lot of the subjective advantage of tube and analog sound
is based on this. Extremely linear phase response throughout the system will
prevent audio superwaves from developing within a system, and this would
explain the perceived advantages of precision capacitors, coils and
conductors.

Mike Csontos

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