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Speaker wire - another fine theory
On 18 Sep 2003 14:45:08 GMT, (Bob-Stanton)
wrote:
The subject
was a transmission line (speaker cable) *not a loop of copper wire*. A
transmission line is two conductors in parrallel, with a termination
at the end. The termination can be any impedance. *Only* if the
termination is a short, will the speaker cable have the
characteristics of a wire 'loop'. If the termination is an 'open', the
line (at audio frequencies) will look like a capacitor. If the
terminated is a resistor (of the correct impedance), the line will
look resistive to the amplifier (not inductive or capacitive).
As the spacing between the two parallel conductors increases, the
capacitance between the two conductors decreases, but the inductance
of each conductor *remains the same*. Only if the termination is a
short, does the loop inductance increase.
While this is all true, the reality is that most speaker cables have a
characteristic impedance of 50-100 ohms, and are connected to a load
of less than 8 ohms driven from a source of less than 1 ohm. To a
close approximation, this *is* a shorted termination.
--
Stewart Pinkerton | Music is Art - Audio is Engineering
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