Mod Garage: A Flexible Dual-Humbucker Wiring Scheme
Get five sounds from your H/H guitar.
If you own a dual-humbucker guitar, here's a wiring scheme for you to consider. Designed to make your guitar more flexible, it's a mod I often perform in our shop, and customers regularly request it. It applies to all H/H guitars that use a Fender-style 3-way pickup selector switch and a master volume/master tone configuration. This includes humbucker-equipped Telecasters, Stratocasters, Hamers, Yamahas, and the like. However, with additional switches you can apply this mod to H/H guitars with a 3-way Gibson-style toggle, such as Les Pauls and SGs.
Most H/H guitars (that is, guitars with humbuckers in the bridge and the neck positions and no middle pickup) have Les Paul-style wiring, with the 3-way pickup selector providing these sounds:
• Position #1: bridge humbucker alone.
• Position #2: bridge and neck humbucker together in parallel.
• Position #3: neck humbucker alone.
While this traditional wiring works well for many players, others would like to have more tones for greater flexibility, or just to have fewer guitars onstage. It's not a new idea: Companies such as PRS, Kramer, and ESP have used similar wiring for many years. This is just one more way to get more tones from an H/H guitar.
What you need. As mentioned, you need an H/H guitar with a master volume/master tone configuration, plus a Fender-style pickup selector switch. Both humbuckers must be four-conductor types because you'll need independent access to both coils of each pickup. If you have vintage-style humbuckers with only two wires, you can either replace them with four-conductor pickups, or convert your pickups to four-conductor specs. (If you're inexperienced in this field, leave this procedure to a pickup maker or guitar tech. The wires inside a humbucker are fragile, and it's easy to destroy a pickup if you're not careful.) If your humbucker sports a metal cover, it must be removed for this operation, which can also be a challenging and delicate task if you lack the right tools and skills.
We'll also be replacing the stock 3-way switch with a 5-way switch with four switching stages rather than the standard two stages. These parts are usually referred to as “super switches." Fender part #0992251000 is a well-known open-frame version.
Other companies such as Eyb and Schaller offer PCB-based versions. You can learn more about these switches and their switching matrices in “Introducing Fender's 5-Way Super Switch" and “Exploring Fender's 5-Way Super Switch." (Oddly, while we often receive requests for 3-way super switches, none are available. They're only made in 5-way configurations.)
It doesn't matter whether you use the open-frame or PCB version. I like open-frame switches because you can clearly see what's going on inside, which can make things easier. On the other hand, the open-frame version is physically larger, so the PCB type may be a better fit for some guitars. (Always check the size of the control cavity before buying such a switch.) Fender's open-frame switch requires at least 21 mm of space, and I recommend at least 25 mm to avoid problems with the soldering terminals.
What it does. This wiring offers the traditional pickup combinations, but adds two additional ones by splitting the humbuckers into single-coils:
• Position #1: bridge humbucker alone.
• Position #2: bridge humbucker, inner coil only.
• Position #3: bridge and neck humbucker together in parallel.
• Position #4: neck humbucker, inner coil only.
• Position #5: neck humbucker alone.
Many humbuckers don't sound like real single-coils in split mode, but at least you get a “single-coilesque" approximation.
Wire it up. After replacing the stock 3-way with the 5-way super switch, you'll wire it up as shown in Fig. 1. (Keep in mind that the diagram shows Seymour Duncan's pickup-wire color code, and that other manufacturers use different color codes.) The wiring as shown uses the inner humbucker coils for split mode, though it's easy to flip to the outer coils by moving only one wire, so try both options and decide which you prefer. You could even add a mini toggle switch to have both choices available. (Personally I don't think it makes much difference.) Remember, when you shunt one coil to ground like this, the humbuckers become “real" single-coils, and the split settings can pick up hum and noise. In a future column on H/H mods, we'll focus on preserving the humbucking operation.
That's it! Next month it's Stratocaster time—I'll show you how to get your Strat close to Ritchie Blackmore's specs. Until then, keep on modding!