How Do Coil Tap & Split Coil Pickups Work?
Coil Tap vs Coil Split – we clear up the differences
In the world of guitars there are many popular myths. Mistruths, wrapped up in half-baked theories, often presented with absolute certainty. Music is, as we know, entirely subjective. Conversations around what is the ‘best’ guitar, for example, are largely moot. However there are certain ambiguous subjects which can be conclusively cleared up.
A prime example of this refers to coil split and coil tap pickups. We’ve all heard the terms used, but there tends to be confusion over what exactly each term means. Are they one and the same thing? Don’t they produce roughly the same result? Let’s examine how coil tap and split coil pickups work.
Perhaps a good place to start is by looking at how a pickup actually works. We know what they are but it’s worth looking a bit deeper in to how they do what they do. Warning; we’re going to use science. We’ll keep it light.
Essentially, a pickup comprises two main components; magnets and copper wire. The thin wire is wrapped around the magnet hundreds (often thousands) of times. As the instrument’s strings vibrate they affect the magnetic field created by the pickup. A small electrical charge is created which is fed to the amplifier, and subsequently to the amp’s speaker cone. From here, sound is created.
There are plenty of variables between pickups. This can be in the magnets used, or in the length of wire wrapped around them. Even be the pattern used to wrap the wire in the first place. Different configurations result in different tones. A powerful neodymium boron iron magnet, wrapped a few thousand times, will produce a strong magnetic field. This results in a powerful, high output tone. Conversely, a cheaper alnico magnet wrapped fewer times sounds much thinner.
To hum or not to hum
The first kind of guitar pickups were single coil. This means they had one coil working with a single magnet. While this serves the purpose of creating a musical signal which can be amplified, it also has certain problems inherent with its design. Chief among these is the fact that single coil pickups act like small antennas picking up, often undesirable, noise. You probably know what feedback is, in pickup terms. When tamed, it is a wonderfully expressive sound but if not it has the potential to ruin a performance. Single coils are also infamous for producing a humming noise, caused by magnetic interference from things like lights or televisions.
To combat this, the Gibson guitar company designed and patented a new form of pickup. Their PAF (patent applied for) design introduced a second coil to the mix. This second coil, wired out of phase with the first one, means the 60-cycle hum is cancelled out completely. For this reason, these new pickups were named humbuckers, on account of them removing the hum. Another benefit was that the increased magnetism also provided a boost to the signal, allowing for thicker tones to be created.
Guitarists, perhaps more than any other musicians, crave versatility from their gear. The ability to switch between different tones is what makes the guitar such an important mix in any band. You’ve probably seen artists change guitars between songs when they perform live. It’s not so easy to switch mid-song though, so sometimes certain solutions are needed to bridge the gap between tones.
A good example of this is the differences apparent in both single coil and humbucking guitar pickups. For certain genres, the glassy cut-through of a vintage single-coil is sheer perfection. For others, there is no substitute for a meaty humbucker. But what about when both are required?
To solve this problem, pickup manufacturers began to tinker with the engineering of their products. Step forward coil splitting and coil tapping…
Split or tap?
To allow guitarists extra versatility from their pickups, many guitars now incorporate either coil tapping or coil splitting. Both allow greater flexibility over the guitar’s output, thus increasing the tonal palette available to the player. But while they sound like two peas in the same pod, they use quite different approaches to achieve their aims.
Coil splitting, the more widely used variant, takes one of a humbucker’s two conjoined coils and shuts it off completely. This makes a decent approximation of a single coil pickup, and allows instantaneous switching between the two, usually via a switch on the guitar itself. The benefit here is that the player can enjoy the best of both worlds with the flick of a switch. The downside is that the 60 Hz hum rears its ugly head, negating one of the reasons to use a humbucker in the first place.
Coil tapping, on the other hand, is employed on both single coil and humbucking pickups. It relies on two separate points within the copper winding being available for connection. In simple terms, imagine a pickup with copper wire wrapped around it 2000 times. Connected to its traditional ‘end’ point, the pickup outputs at its fullest potential. In a coil-tapped pickup, there is a second connection point made available halfway through the winding. In this example after 1000 winds. The signal output from this point is clearly going to be different, and may be desirable for certain tones. Using this approach you can install a higher output single coil, but still have the vintage tones associated with lower output pickups available to you.
In reality, truly coil tapped pickups are not as widely used as coil split pickups. Often coil-splitting is added onto humbucker equipped guitars and is seen as a ‘nice to have’ feature, although not generally essential. In a studio setting, for example, a guitarist with an arsenal to choose from would almost always choose a dedicated single coil guitar over a coil-split humbucker guitar. But for on-stage versatility, and the extra tonality they provide, these added features open up a world of new possibilities for you to use.
Take a look at a full range of electric guitars over at the Dawsons website.