When you're new to guitar, there are many mysteries that you solve the longer you play, the more gear you're exposed to and the more you practice. The subject of pickups is one you should be well versed in from the start, as your guitar's pickups are arguably the most important factor in your tone. While other factors like the tonewoods used, the weight of the guitar, the amp you use, etc. have much to do with your sound, knowing a little about pickups can help you hone in on your own signature sound. Though there are variations and specialty types as well, there are three basic types of pickups you'll encounter on most electric guitars: single coil, humbuckers and piezo.
Single-coil pickups feature a single magnetic bar that is wrapped in fine wire and mounted beneath and perpendicular to the strings. The fine wire is what picks up the signal and sends it out of the guitar. Single-coil pickups were the earliest of the three most common pickups. They produce a bright, cutting tone rich in higher harmonics. The simplest versions—still found on many guitars and preferred by many players—produce an audible 60-cycle hum when in the presence of certain types of lights, transformers, and other electrical fields.
An EMG S2 Single Coil Pickup
Humbucking pickups, AKA humbuckers, feature two coils wrapped opposite from each other, eliminating that annoying 60-cycle hum. Since the humbucker samples the string in two places—once for each coil—it generates a smoother, rounder tone. And since there are two magnets involved, humbuckers usually generate a more powerful signal, giving the amplifier more to work with.
A Gibson ’57 Classic humbucker
Humbuckers tend to generate more sustain than single coils, but with less note definition and high end. Some humbuckers are available with a coil-tapping control, which allows you to opt to use only a single coil in the pickup, thus generating the characteristic single-coil sound.
Piezo pickups are made of a non-magnetic crystalline material that generates an extremely weak signal when compressed in the string saddle. This faint signal requires preamplification before it's ready for a normal amplifier, usually accomplished by onboard active electronics. On electric guitars, piezos are typically individual elements incorporated into the string saddle. Some electric guitars with piezos have special 13-pin outputs for synth guitar, in which the guitar's signal triggers purely synthetic tones as on a keyboard. Otherwise, the piezo tone is often used to approximate the sound of an acoustic guitar.
Swapping out your pickups is a great and inexpensive way to breathe new life into a guitar that just isn't cutting it tonally. Less-expensive guitars are often built in the same factories or use the same raw materials as their high-end counterparts, with cost saving done on areas like the hardware, pickups, and visual appointments. Many players have taken these guitars and "hot-rodded" them with new pickups, making them tonally diverse and ready for the stage—you can too! Either way, if you're not satisfied with your tone but love the playability of your axe, a new set of pickups is probably in order. It's not always feasible to change pickup types in an instrument, but there are certainly enough flavors of each kind available that finding the tone you're after shouldn't be too hard.