What about phase shift due to frequency dependent travel times down the speaker
cable? Measurements show that 100 Hz waves will be delayed about 20 billionths of a
second behind 10 kHz waves when traveling to the end of a 10 foot speaker cable.
Since the cilia of the ear requires 25,000 times longer than this just to transmit phase
information, phase shifting is obviously not the primary concern when considering
speaker cables.
What about resistance? Finally we are getting somewhere. Resistance is the control-
ling factor of the amplifier/loudspeaker interface. Excessive resistance can cause ma-
jor shifts of speaker crossover frequencies. The lower the impedance of the loud-
speaker, the greater the effects of series resistance. A 20 foot run of 18 gauge cable
can cause up to 10% deviations of crossover center frequencies. That same 20 feet
can un-damp your damping factor and reduce your systems’ output by onehalf deci-
bel.
In summary, there are no perfect cables. The best way to approximate the ideal
would be to keep loudspeaker leads as short as is practical.
Hooking Up Cables
12
