Two-humbucker guitars are great, but with just a 3-way switch, you might think that the tonal options are somewhat limited. There are, of course, many things you can do to get more sounds out of dual-coil pickups. This should give you an idea of what some of the options are and what they sound like.
The most common mod is to cut one of the coils. That will certainly give you a different sound, but remember: Half a humbucker does not a single-coil make. A split coil rarely sounds like the sweet single-coil pickup you wished it did—it’s usually too thin, too bright, and not as loud as a true single-coil. So, what can you do about it?
The easiest thing to do is to modify the coil you are cutting. There are two ways to cut a coil: You can ground one of the coils out by moving the ground or you can move the output to select the opposite coil. When you ground out a coil, you can choose to not fully ground out the entire coil. You can run the coil through a capacitor to ground. Try values around .01uf to .05uf for starters. This will filter off the treble frequencies of the one coil, allowing the bass frequencies to interact with the existing coils. This leaves you with a little more volume and a tone closer to a P-90. Unfortunately anything short of matching coils begins to lose the hum-canceling benefit.
Another trick is to put a resistor between the coil cut point and ground. This will control how much of the coil you are removing. I like to put a trim pot at that point so I can tune it by ear. Once I have it dialed in, I can measure the trim pot and replace it with a resistor or just leave it in place for further adjusting. If you have an extra control on your guitar, you can set that up for an onboard variable coil cut. On any guitar with two tone controls, it’s easy to convert one tone control to a master tone and then use the other one for a variable coil cut knob.
The coils of a humbucker are normally wired in series. Switching them to parallel operation is a cool way to get a new sound, and this is easily accomplished with a humbucker with four-conductor wiring. A humbucker in parallel sounds similar to a single- coil, but with no hum. You can switch between series and parallel operation with a pushpull pot, a mini-toggle, or a 5-way switch.
Here is an odd trick that is a little more work but can make an interesting difference. Many dual-coil pickups have polepieces you can remove. On a Gibson-style pickup, the screws come out easily. You can get the slugs out by carefully removing the two screws that hold the coil in place, then slightly heat up the coil with a hair dryer or lighter, lift the coil, and pull the slugs out from the back. (Keep in mind, of course, that any tampering with a pickup can kill it.) We have experimented with removing three from one coil and three from the other, and it was a good way to clean up and remove some mud from a dark-sounding pickup. While you are playing with the polepieces, try lowering the pickup and raising the polepieces for more clarity.
One last idea to put out there is the concept of adding wire to one of the coils. The extra winds only come into play when you switch to single-coil mode, giving you a fatter tone. In normal humbucker mode you’re still just using the original coils.
These are just a few of the ways you can get more sounds out of a dual-coil pickup. Don’t let that 3-way switch fool you. There are a ton of tones lurking in that humbucker guitar.
Gary Brawer is bald, he’s bad, and he gives a sh*t about your guitar. His many clients include Joe Satriani, Metallica, and Neal Schon.