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Gibson's twin-pole pickups-often called humbuckers (as they "buck the hum)
Were created by Gibson in the mid-1950's. They were designed to prevent hum and
other forms of electrical interference. Humbuker have two set of coil in each unit,
wired up so that they are out of phase. This means that any interference reaches
one coil in a positive signal. The theory goes that when identical positive signals
are received at the same time, the one cancels the other out.