Out-of-phase sound?

I'm just on my laptop right now, but yeah that doesn't sound like a phase switch. I'd bet it's a series/parallel switch, or perhaps a coil split switch.

 

Agree 100% here. Putting both pickups out of phase would sound exactly the same. Putting the two coils in a humbucker out of phase would greatly reduce the output.

 

Humbuckers are made with the coils out of phase, that's how they cancel out any electromagnetic hum fields. Putting the coils in phase will just give you an ordinary single wound coil, with another inductor which will load the signal, and also pick up even more extraneous hum. Not very useful, in my books.

 

Either coil OOP with the other oil in a humbucker would produce a weak sound in both series or parallel.
Guitar Wiring Site - How A Humbucker Works

 

I added a “phase switch” on a couple of basses, a Fender Jazz and an Ibanez RB850. In the picture you can see the small switch on the Fender.


The switch inverted just one of the two pickups. The result in sound was a kind of a deep scoop of the middle frequencies. Instead of the two pickups signal sum you get a kind of subtraction: what is “same” signal on both is erased, so in the output you just have the difference between them. The effect is maximum when both volume pots are fully open, anyway tweaking the pots some very interesting result could be obtained. It is almost the same principle used on helicopters microphones for noise cancelling.

 

I performed the same modification on an Ibanez RB850, equipped with two humbackers very similar to the MM. The effect is very strong with the balance between the two pickups at maximum, but it can be modulated by playing on the difference in volume between the two pickups.