Most guitar players are more interested in how guitar pickups sound than how they work, but understanding the magic behind the scenes can be crucial for choosing the right model and deploying it in practice.
In short, the hardware components of an electric guitar form a complex system, with pickups at the focal point. They generate and later amplify signals from vibrations created by strings being strummed, but this oversimplified explanation doesn’t even scratch the surface. Let’s dive deeper into how guitar pickups work.
Guitar Pickup Architecture & Makeup
To understand how anything works in the vast world of modern electronics, it’s best to pick it apart first.
Electric guitar pickups are inductive sensors made of coils wrapped around magnetic poles. Depending on how many coils a pickup has, we have the infamous “single-coil” and “dual-coil” pickups.
The other essential piece of the puzzle is the material of the strings on your guitar. Regardless of the layers and core, all strings are ferromagnetic, or more specifically, they feature ferrous alloys.
Coils are typically made of copper wire. When you wrap copper around magnets, you get a generator. The basics of electricity dictate that when generators with magnetic fields come near ferrous materials, alternating electrical current is made.
Strings Interact with magnets to generate an electric signal
The main reason why we, as guitar players, are required to strum the strings to create that beautiful “electric” guitar sound is that pickups need vibrations to catch and later amplify electrical signals.
In layman’s terms, magnets wrapped with copper coils have a certain radius in which their magnetic field exists and functions in “harmony”. Electric guitar strings themselves become magnetized when plucked and affect the shape of the magnetic field generated by coiled magnets.
The intersections and interactions between the two fields are ultimately what create the electric signal.
Guitar Amps do the heavy lifting
Electric science tells us that the signals created by interactions between guitar string vibrations and pickups are neither strong enough nor adequately “shaped” to produce a proper tone. That’s why we use guitar amplifiers.
It’s the preamps found in all guitar amplifiers that receive the created signal first. Preamps boost this electrical signal and flush all unwanted noise away before funneling this “reshaped” signal down the line.
The next step in the signal’s route takes us to the “power amp”. Even with a hearty “boost” from the preamp stage, the signal coming from the guitar’s pickups is still too weak for practical application.
Power amplifiers take the raw signal from the preamp and generate a bigger “copy” of the data, making it far more manageable for actual tone customization.
With a neatly polished signal at our disposal, we are free to shape it to our preferences using the equalizer knobs to fine-tune desired frequencies, introduce (or cut) gain, and layer the sound with pedal effects.
Conclusion
The most fascinating thing about the system by which guitar pickups work is that countless operations are conducted in the blink of an eye.
A single strike on a (ferrous) string helps pickups generate a faint but usable signal, which is then pushed through multiple avenues before it becomes what we ultimately hear from our headphones, speakers, or the amp directly.