"The majority of current flowing between an amplifier and speaker is devoted
to bass reproduction. In fact, 60% or more of an amplifier’s output is destined
for the woofers. When current flows through a wire, it produces an
electro-magnetic field (EMF) that expands and collapses at a rate equal to
that of the music’s complex frequency components. If a single speaker
wire must conduct the full musical frequency, the preponderance of lowfrequency
information can interact with or modulate high frequencies.
The resulting intermodulation can create audible changes to the high
frequencies even before they reach the loudspeakers.
By using separate cables for high and low frequencies, unwanted high-
frequency modulation is avoided. Low-frequency information flows
through one cable while high frequencies flow through another.
Having the opportunity to use separate low- and high-frequency cables
allows you to use cables best suited to each frequency range. Optimally,
you should use high-quality, audiophile-grade speaker cables for both lowand
high-frequency conductors. However, let your ears guide you to the
Frequency-optimized Cables.""
From the JBL 4344Mk11 owners manual.
IMHO if you had a blameless amp and blameless cable none of this would be an issue. Keep your cable short and stout and use an amp with a high damping factor at all frequencies, not just tthe low bass at 20hz.
Some amps will react to the back emf anyway and this is one of the key reasons systems with large woofers seem to benefit from true biamping.
The back emf of the woofer can also make its way into the mid range crossover filter in full passive mode and cause intermodulation issues unless carefully designed. (most of the 43XX series).
Its a case by case thing.
Ian