By Tom Spaulding and
Planet Waves
They’re everywhere – stuffed into gig
bags, hanging on the wall, crammed into the back of
your combo amp. Cables are the lifelines of your
music and learning a bit more about their
construction, and the difference between a low
budget cable and one designed for premium audio
applications is worth the effort.
Every time you plug in a cable from
your guitar to your pedalboard or from one stompbox
to the next, you expose your audio – your music – to
interference. Buying the right high quality cable
will ensure that your music gets to the ears of your
audience sounding the same as it did when you
imagined it in your head… and played it on your
instrument.
A basic guitar cable consists
of a pair of copper wires, one hot and one
ground, which is wrapped by a sleeve of
metal foil, spiraled wire or braided wire
called the shield. The shield is used to
reduce incoming noise such as RFI and EMI.
RFI is radio frequency interference,
and you have probably heard a radio station coming
through your amp at some point, likely do to a bad
cable.
EMI is electromagnetic interference,
the buzz or hum caused by electromagnetic fields
like power lines and lighting dimmer racks.
A third type of noise is called
triboelectric noise, often referred to as “handling
noise”. If you have ever picked a cable that was
plugged in and heard snaps, cracks and pops, that is
the sound of electrical charges being transferred
into the cable. Planet Waves uses a conductive PVC
layer of insulation that dissipates the charges,
which keeps the noise level down.
Two types of cable are used to combat
the noise from these sources. Coaxial cable is
designed so that the shield and the conductor carry
the same current. The magnetic fields cancel each
other out, and since no field is being produced, it
can’t pickup noise from external sources. Coax
cables excel in rejecting electrostatic noise. This
is the design technique used in the premium Planet
Waves cables.
The other cable type is called a
‘twisted pair”. The twisted pair refers to two
coated wires wrapped around each other. Due to their
close proximity, any noise that is picked up by one
wire is cancelled by the other wire, and noise is
minimized. This is a less expensive solution, and
offers nearly the same performance as the coax
cable.
For
everyday gigging, a twisted pair cable is fine, for
critical audio (recording studios, audiophile
systems) coaxial cable is the best solution.
Article provided by
Planet Waves, maker of high quality instrument
cables and accessories.
Visit them at
www.planetwaves.com.
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