Written by Bobby
Parent article: Best Guitar Pickups
In this article we're going to look at the question:
How do guitar pickups work?
While there are some technical issues that need to be understood, guitar pickups and humbuckers can also be explained in a straightforward manner. We'll look at this simple explanation as well as some of the most relevant technical details and even a little bit of the science involved.
In this context we're talking about magnetic pickups, which are most common in electric guitars and basses.
If you're in the market for a new tone, checkout our best guitar pickups roundup page for some recommendations.
How do guitar pickups work at a basic level?
Pickups are basically magnetic poles that attract the steel and nickel in guitar strings. When an electric guitar string vibrates, it disturbs this magnetic field which, based on Faraday's law of induction, creates an electric current that moves through a coil wrapped around each magnetic pole. This eventually becomes the sound we hear through an amplifier.
Once the coil around each magnetic has created the electrical current, the pickup's share in the process is finished and the signal gets passed through the electrical wires, the instrument cable, and - eventually - into an amplifier.
Let's look a little closer at Faraday's Law.
What's the science behind FARADAY's LAW?
Faraday’s Law of Induction reads like this:
Any change in the magnetic environment of a coil of wire will cause a voltage to be "induced" in the coil.
This of course depends on the surface area of the magnet, the strength of the magnet, the type of magnet, and the vibrations of the strings or the degree of disruption of the magnetic field.
- The surface area of the magnet
- The strength of the magnet
- The type of magnet
- The vibrations of the strings
- The degree of disruption of the magnetic field
While the mathematics around this can get somewhat complicated, this is the basic science behind the interaction between the strings and magnets.
In terms of understanding pickups and how they work, it's the core of what's happening.
The following graphic shows a simple depiction of a guitar pickup from a side view with a magnetic poll, coil wrapping, and the magnetic field around a guitar string.
We've already established that guitar pickups consist of small magnets, but what else is used in their construction?
First, you have the magnetic poles lined up under each string. These polls are then wrapped in a small coil of wire (usually copper wire), and encased in some kind of pickup cover. Connection wires are then attached to each pickup, which can then transmit the electrical current to the instrument cable jack.
This gives us four essential components:
- Coil or wrapped wiring
- Connection wires
The coil we mentioned, wrapped around the magnetized pole piece, becomes the receiver of the disruption or "magnetic flux" being created by the portion of the string that's being pulled by the magnet.
Most of what you see when you buy a guitar pickup is that outer covering, which can have a small impact on the pickup's tone.
Almost all guitar pickups use one of two types of magnets:
While there are different kinds of Alnico magnets, "Alnico" is often considered its own category.
The two listed above are the only major categories of magnets used for building pickups.
Alnico magnets are typically used in Stratocaster pickups and similar single coil rails. They produce a brighter and more bluesy tone that's often used in vintage guitars and playing styles.
Ceramic pickups are more often seen in humbuckers and produce a smoother, more modern sound that is often desirable for distorted tones and heavier playing.
Other than the type of magnet and the electrical/magnetic process, the functionality of a guitar pickup and humbucker is really straightforward.
Just to recap, you have the magnetic field, disrupted by steel string vibrations, and then the coil wrapping that transmits the resulting electrical current. In simpler terms, they translate the vibrations of the strings into a current that can be carried by an instrument cable.
Though the science can get really deep, the practical aspect is super simple.
Still got questions?
This is a topic that is somewhat new to me.
Like most who play electric guitar, I just assume the entire thing works.
Rarely do I ask the question, "How do guitar pickups work?" I just trust that they do and then use them accordingly.
But if you have lingering questions, leave them in the comments section below and I'll do my best to help out. What I love about the Guitar Chalk comments section is that I'm often able to learn with readers and we're able to help inform one another.
See ya there.