Parallel Wiring

Parallel wiring is the most common way to add multiple pickups together. The selector switches in traditional Fender and Gibson guitars choose individual or combined pickups in parallel.

Pickups are normally combined so that the polarities match. A "hot" lead should connect to another "hot" lead, and ground leads should tie together. This normal type can be called "parallel-aiding" since the two signals will match each other fairly closely.

Pickups can also be combined in "parallel-opposing." Swapping the leads around on one pickup in a parallel-aiding wiring would result in parallel-opposing. This is more commonly called "out-of-phase" wiring and has its fans although the resulting signal is weak and thin due to the opposing signals canceling each other out.

A notable "octave up" special effect can be achieved by parallel-opposing a humbucker and playing about the 12th fret.

Most guitar techs get a grip on parallel wiring intuitively. Much more interesting and/or confusing is series wiring.