8
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 controlling factor of the amplifier/loudspeaker interface.
Excessive resistance can cause major shifts of speaker crossover
frequencies. The lower the impedance of the loudspeaker, 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 one-
half decibel.
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.
