Series and parallel wiring refers to how two coils in a humbucking pick up are connected to each other. With series wiring the individual coils are connected end to end. This is the most common way. humbucking pickups are wired. With parallel wiring the individual coils are connected to each other at both ends and current flows through both coils at the same time. Pickups wired in parallel are brighter sounding and have considerably less output than an identical pickup wired in series. They can be switched using a push/pull pot.
The terms series and parallel are also used to describe the way in which separate pickups are connected by the selector switch on the side of your guitar. most of it are connected in parallel but connecting 2 pickups in series result in greater output.
If you want to have phasing, it means that you can choose two pickups wired such that they "fight" each other. It basically means the signal are out of phase, as such the resulting sound is thin and trebly. I've heard that selecting a neck and bridge pickups out of phase when using hot pickups, the result is some sort of a sort of "hollow" tone. Sound interesting but i've not heard that tone before.
If you want to listen to out-of-phase sounds, just switch your leads on your middle pickup and listen to the 2 and 4 positions on your selector switch
Hope this helps
