Quote Originally Posted by Eric View Post
...So I take it you will need to do some of the more intense modifications you touched upon in your other thread, yes? Do you need to do any flipping or swapping of pickups or anything due to the polarity differences or anything?
In this case, all I needed to do was switch the hot & ground connections for the DiMarzio humbucker vs. the stock installation instructions. Not only does that put the humbucker output in phase with the output of the CV Strat's neck and middle pickups, but it will also keep the #2 position of the pickup selector hum cancelling when the humbucker coil is split. This is important to me because I will next be wiring the 5-way switch so that the coils are automatically split at position #2, to get the "max quack" from the bridge-middle pickup combination.

Depending upon the phase and magnetic polarity of the middle single coil in a Strat or similar guitar with single coil pickups, you can run into four possible combinations of the signal phase and magnetic polarities with a split-coil humbucker. It can be:

  1. In phase with the middle pickup and hum cancelling (the desired case)
  2. In phase with the middle pickup but not hum cancelling
  3. Out of phase with the middle pickup but hum cancelling
  4. Out of phase with the middle pickup and not hum cancelling (a total FAIL!)


Fortunately, with a 4-conductor humbucker of the type you use for coil-splitting, any of these four are possible, depending on how the 4 leads are connected to the switch and to each other (i.e. the "series link" between the two humbucker coils). As long as you know how the coils of the humbucker relate to the middle single coil, both in terms of signal phase and magnetic polarity, you can wire in the humbucker to get that "desired case" output. And the phase and polarity are easily determined by simple test methods before you make the connections. That's how I determined that I needed to swap the hot and ground leads when I installed the Air Norton last night.