Fig 1. (Above) The switching matrix for this project’s on/on/on switch, as seen from underneath the unit.
Fig 2. (Right) The schematic for wiring a DiMarzio Chopper bridge pickup to an on/on/on switch. Remember, the pickup’s bare ground wire also goes to ground.
Now, let’s go one step further and discuss a strategy to enhance the tonal palette even more, using a scheme I sometimes call “ultra-flexible” wiring. Essentially, the idea is to squeeze as many useable sounds as possible from a single-pickup Esquire. To give you a real-world example, I’ll explain how our shop uses this scheme on one of our custom Esquire-style models called the “Mnajdra.” But I’ll also explain the principles behind ultra-flexible wiring, so you can add this feature to any Esquire wiring of your choice.
As we saw in last month’s column, you can get three basic tones out of a humbucker that offers 4-conductor wiring: both coils wired in series (normal humbucker mode), both coils wired in parallel (this yields a hum-free, single-coil-like sound), and coilsplit (a true single-coil mode achieved by shutting down one of the coils).
Is it possible to get even more sounds out of a 4-conductor humbucker? Yes, but not every option makes sense in a musical context. To understand why, let’s be more precise regarding the basic tones we just described. From an electrical point of view, they are: both coils wired in series (in phase), both coils wired in parallel (in phase) and coil-split (lower coil).
You guessed it: There are three additional sounds you can coax from a 4-conductor humbucker: both coils wired in series (out of phase), both coils wired in parallel (out of phase), and coil-split (upper coil). This expands the tonal palette to a total of six basic sounds from only one pickup. By the way, the coil-split mode is always in phase, simply because there’s only one active coil and nothing to be out of phase with.
To access these three additional sounds, you can use a complex rotary switch, a 5-way super-switch with four independent stages (aka “4x5 switch”), several mini switches mounted on the control plate, or push/pull or push/push pots with a DPDT switch.
While it’s electrically possible to add the three extra sounds, in my opinion they’re not really useable. For starters, in the coil-split mode, the difference between engaging either the lower or upper coil is barely noticeable—the coils are simply too close together to make a big sonic change.
It’s the same with the two out-of-phase options. It’s true that switching the phase between two pickups that are separated by some physical distance can sound very cool. This is because of the phase cancellations that occur due to the pickups’ different locations. However, the two coils within a single humbucker are physically close, and this yields only a minimum of phase cancellation. Sonically, the effect is very subtle— especially on a humbucker that’s designed to fit into a single-coil space.
To access the three most useful sounds from a 4-conductor humbucker, I suggest adding a 3-way on/on/on mini-toggle switch. This keeps the Esquire’s standard 3-way pickup selector free for other uses. (Stay tuned for details in Pt. 2 of this column.) On an Esquire or Telecaster, there’s plenty of space on the control plate between the two pots for this kind of switch.
A bit more expensive than standard switches, the mini toggle we need has two stages and a special switching matrix. Fig. 1 shows this matrix, as seen from below. There are several on/on/on switches available, so make sure to get the right one.
You can easily install this switch on the control plate between the two pots by drilling a 6 mm hole exactly in the middle of the plate. This new switch can substitute for the standard 3-way pickup selector by taking over its functions. This way, you can dial in the desired pickup operation mode with the new switch, then add your favorite Esquire wiring after the switch.
It’s important to understand that the new switch is wired ahead of the stock 3-way switch, so the pickup is directly connected to the on/on/on switch, and it receives the signal before the pickup selector switch. You can orient the new mini toggle on the control plate so the switch works up/ middle/down (my preference), or turn it 90 degrees for left/middle/right operation.
Now you need to know how to connect the wires from the pickup to the switch. To illustrate, I’m going to use the DiMarzio Chopper bridge pickup that I described in depth last month. Fig. 2 shows the wiring using DiMarzio’s color code. If you use a different pickup—and that’s not a crime— you’ll have to convert the color code first to make the schematic work properly.
Naturally, the pickup’s bare ground wire goes to ground. Note the black jumper wire on the switch: Don’t forget to solder it—this is very important for the on/on/on switch to function properly.
By simply mirroring the diagram, you can decide if you want parallel or series in the up or down position (or respective left or right position, depending on how you physically orient the switch). If you don’t want the coil-split option in the middle position, you can figure out how to rewire the switch to put coil-splitting in the up or down location. Simply use the diagram in Fig. 2’s switching matrix to work this out.
Next month we’ll conclude our exploration into this Esquire-meets-humbucker topic by combining the on/on/on switch with a flexible Esquire wiring. This project yields a total of nine different and useable tones from a single pickup. Until then, keep on modding!
Dirk Wacker lives in Germany and is fascinated by anything related to old Fender guitars and amps. He plays country, rockabilly, and surf music in two bands, works regularly as a session musician for a local studio, and writes for several guitar mags. He’s also a hardcore guitar and amp DIY-er who runs an extensive website—singlecoil.com—on the subject.