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(Dick Pierce) wrote in message

BTW, have *you* EVER bothered to see if your "theory" results
in predictions that you have then compared with ACTUAL
measurements?

Thank you for again giving me credit for creating established
transmsission line theory (by your calling it "your theory").

I don't feel it is necessary for me to reprove basic transmission line
theory. The basic theory could be wrong of course, but I'll leave that
up to you to prove by measurements.

I'm curious to see what you used as a lumped
constant model. Please show us a model of 100 ft of standard (Home
Depot), 12 gage cable (terminated by an ideal 8 Ohm load).

Please show us who is using 100 ft of standard (Home Depot)
12 gauge cable in a typical home listening situation.

Please show us ANYONE whose speaker cables are terminated by
an ideal 8 ohm load.

I was just trying to keep the problem as simple as possible. The
termination value is irrelevent since it doesn't change the
transmission line itself.

So Dick, since no one has put forth a lumped element, transmission
line model, perhaps you would like to show us one.

Mr. Stanton, your model is **** NOT because its a transmission
line or any other model, it's **** becuase of your grossly incorrect
assumptions and the fact that these assumptions simply don't exist
in actual situations.

Any real-world cable and any real-world speaker-impedance can be
*easily modeled*.

And that is yet more evidence of how far from physical reality
your "model" is. I have presented a NUMBER of lumped parameter
(not "lumped constant") models, as each and every speaker system
presents a significantluy different load.

That is correct, even if it is rather obvious.

So, let's review your assumptions behind your "model" once again:

1. You assume that people are using 100 feet of cable.
But people VERY RARELY use 100 feet of cable, it's more
typically 1/10th that distance, making the necessity of
a transmission line model even more irrelevant and
unnecessary.

10 ft is fine. One can model a transmission line for X number of ft.

2. You assume that the cable is terminated by an ideal
8 ohm load.
But NO speaker is anything approaching an ideal 8 ohm
load.

One should use an ideal load when measuring any cable's
characteristics. By making the computer model with an 8 Ohm load, the
computer's results can be compared to actual measurements.

3. You have looked at ONE example of a non-ideal load.
But, apparently, you have never incorporated such a non-
ideal load in ANY of your models.
Further, you have apparently ignored the fact that one
lumped parameter model simlpy is not representative
of the enormous variations in actual speaker loads.

Any real-world speaker-impedance can be modeled with a one-port (data)
device.

And, finally:

4. You have never once presented a single shred of physical
evidence in support of your "theory" that demonstrates
its superiority or even its very efficacy. You insist
your "theory" is right, but are unable or, more likely,
simply unwilling to do ANY of the work YOU need to do
to support it.

YOUR theory, based on your gross missapplication of transmission
line principles, your preposterous assumptions of operating
conditions, and your long-demonstrated inability to relate it to
any real-world performance issues indeed makes YOUR theory useless.

Any cable, driving any speaker, can be modeled using "one-port" and
"two-port devices". One simply measures the S-parameters (or the
Y-parameters) of the speaker-cable and then creates a two-port (cable)
device. One then measures the impedance of a speaker and creates a
one-port device. Put the two devices together, and you'll get an
accurate model of real-world performance. If you doubt this, maybe you
should go back to school. Perhaps your knowledge of circuit analysis
is a little out of date?

Bob Stanton