FAQ
http://www.seymourduncan.com/website...tml#outofphase
What do in phase and out of phase mean?
Phase refers to the relationship of two sine waves (signals) to each other. If both signals are at their highest peak (+) at the same time they are in phase. If one signal is at its highest peak (+) while the other signal is at its lowest peak (-) they are 180 degrees out of phase. While a complicated and lengthy explanation of this phenomenon is possible, guitar electronics are fairly simple and a basic understanding goes a long way to ensuring your guitar works properly.
Humbucking pickups have the individual coils connected in opposing phase and each coil uses opposite polarities of a single bar magnet. If either of these two conditions is not met the resulting tone will be thin and nasal sounding. It is the combination of these two elements that give a humbucking pick up it's strong full tone with the majority of hum being cancelled The same thing applies to single coil pick ups. It is the combination of opposing phase and magnetic polarity between a RwRp single coil and a standard single that causes the combination to be noise canceling.
How can I tell if my pickups are out of phase?
With two humbuckers connected by a switch in phase pick ups will sound normal, while out of phase humbuckers will sound weak and nasal. This is because out of phase humbuckers result in a lot of low and mid frequency cancellation. With Strat and single coil type guitars being in phase is the problem and if adjacent pickups are in phase the combined selection will not be noise canceling.
This may be a confusing explanation. What we need to emphasize here is that humbuckers work because the coils are out-of-phase and the magnetic polarities are opposite. Either condition by itself will produce conflicting (out-of-phase) string signals from each coil that will result in a thin, nasal sound, but the two conditions together produce a full and powerful string signal and cancellation of most of the hum.
How can I correct out of phase pickups?
With humbuckers it can be as simple as changing the hot and ground connections or flipping the magnet. To correct phase problems with single coils is harder because the pick ups must be both magnetically and electrically out of phase, and it is next to impossible to change the magnetic orientation in single coil pick ups unless you have a magnetizer
