The tonal values of a guitar's sound can be affected by tons of factors. One of those factors is the type of pickup(s) installed, specifically in the case of electric guitars and basses.
How do different types of guitar/bass pickups affect tone? The tonal impacts of pickups are caused by different internal and external configurations and materials that alter the output signal's volume, frequency response, and sustain and noise cancellation. Pickups work with other components that should be factored into the overall tone of a guitar/bass.
We'll be going into detail regarding the elements present in pickups that shape the tone of guitars and basses. For that purpose, we'll discuss how pickups generally work along with the main parameters that influence a pickup's functionality and overall sound.
• Top 11 Benefits Of Learning & Playing Guitar
• Top 11 Benefits Of Learning & Playing Bass Guitar
• Top 3 Factors That Give Guitar Pickups Their Tone/Sound
• How To Improve The Sound/Tone Of Guitar Pickups
• Top 11 Best Electric Guitar Pickup Brands On The Market
• Top 8 Best Bass Guitar Pickup Brands On The Market
• Top 8 Best Acoustic Guitar Pickup Brands On The Market
How Do Pickups Work & What Are The Different “Types?”
It bears repeating that pickups can affect the tone of a guitar or bass depending on certain internal and external features. Nonetheless, we should first understand how pickups generally work to grasp the reasoning behind these impacts better.
Pickups, in short, are the devices that replace the usual soundbox present in hollow-bodied guitars (such as classical and acoustic guitars) in order to produce resonance.
Rather than increasing the resonance and volume of sound waves, pickups are transducers that convert the energy from the string vibrations into electrical signals, known more aptly as audio signals. These audio signals can be manipulated, amplified, recorded, and ultimately reproduced as sound waves through speakers and headphones.
There are different types of pickups, depending on the mechanism, design, and components.
Pickup Transducer Types
According to the underlying transducer technology, pickups can be separated into three different types:
Magnetic pickups: the most common pickup type. They work by way of electromagnetic induction. These pickups create a magnetic field with the metal strings. Instead of relying solely on air molecules, the strings' vibration disturbs said magnetic field, generating electric signals that travel through the wiring until arriving at an amplifying device, responsible for reproducing the audio as sound waves with greater loudness. They can be likened to antennas that capture surrounding vibrations.
Piezoelectric pickups: they have a similar mechanism, but they use crystals introduced within the device to produce the output signal instead of employing electromagnetic means. The piezoelectric crystals produce a voltage as they're compressed and stretched due to the instrument's vibrations. These pickups are normally used as add-ons in electric guitars or as the main pickups in electro-acoustic guitars.
Optical pickups: these pickups are much less popular. They use infrared sensors/photodetectors to read the strings' movement and produce a coinciding audio output.
Pickup Types By Number Of Coils
Pickups can be separated into two general types based on their coil setups. There are others (P90, Z-shape and triplebucker, to name a few), but the following two are by far the most common:
- Humbucker (Dual-coil)
Single-coil pickups: as the name suggests, these pickups have one coil of wire around their magnet.
Humbucker (Dual-coil) pickups: humbucker pickups have two coils, each wound counterclockwise around its own bobbin and magnet. One magnet has its north pole facing the strings, and the other has its south pole facing the strings. The signals from the coils are summed together out-of-phase to increase the signal from the strings while rejecting the EMI thanks to common-mode rejection.
Pickup Types By Magnet Type
Pickups can also be categorized according to the type of magnet employed in their build. The magnet types vary in their exact composition, but the most common types (excluding neodymium, which can be used in bass guitars) are:
Alnico pickups: these pickups utilize AlNiCo magnets, which are alloys made primarily of iron with aluminum (Al), nickel (Ni) and cobalt (Co). The alloys also include copper (Cu) and sometimes include titanium (Ti).
Ceramic pickups: also known as ferrite magnets, ceramic pickups utilize magnets made of strontium carbonate and iron oxide, often with barium, manganese, nickel, and zinc.
Pickup Types By Circuitry
Pickups are also commonly distinguished in regard to their circuitry, namely whether they're active or passive.
Passive pickups: passive pickups convert string vibrations into electric signals and immediately output the signal.
Active pickups: active pickups convert string vibrations into electrical signals, which are then passed through a preamp to amplify, EQ, filter EMI and adjust impedance before being outputted.
The pickup's build quality and architecture will determine how the sound is produced and ultimately heard, but, at times, some enhancements can be applied at the expense of other traits, which is why there is no one-size-fits-all solution.
How Do Different Pickup Types Affect Tone?
Below, we'll look at some of the parameters involved in a pickup's performance. Namely the following:
The immense majority of electric guitars and basses are built with magnetic pickups. Nevertheless, finding guitars or basses with piezoelectric or optical pickups is not that difficult.
Hybrid guitars carry both magnetic and piezoelectric pickups, as well as a switch to alternate between the two or a combination of both inputs.
To learn more about pickup switches, check out my article How Do Guitar Pickup Switches Work & How To Use Them.
Magnetic pickups are standard for electric guitars and sound relatively clean, thanks to the individual pole pieces designed to capture each individual string.
The tone of electric guitars is very much dependent on the pickup versus acoustic instruments, which largely depend on their incorporated tonewoods and body designs.
The actual tone of magnetic pickups is hard to describe due, in large part, to their ubiquity. The magnet type, location, number of coils, inclusion of a preamp, and other factors affect the tone of magnetic pickups. However, there are no strong defining characteristics of magnetic pickups as a whole.
According to many, piezo pickups sound closer to the acoustic experience since they convert the vibrational energy from the bridge and soundboard into audio. The bridge and soundboard vibrations are ultimately the sound waves projected from the guitar (rather than the vibrations of each individual string). This allows piezo pickups, in theory, to produce a truer representation of the real sonic character of such acoustic instruments.
The piezo pickups are not easily seen because they usually reside under the bridge or saddle.
Piezo pickups, as opposed to magnetic pickups, don't emphasize the metal string's vibration over other surrounding motions. Rather, they capture every vibration with equal intensity, owing to the fact that there is no magnetism involved in the process.
These have many benefits over magnetic pickups, such as better sustain, cleaner sound with no interference, and a broader frequency range. However, they are far less common, don't work as well with distortion, and are buggier at higher temperatures.
Number Of Coils
Magnetic pickups may have different coil gauges, windings, and quantities.
Generally, more windings yield a stronger output with the increased risk of electromagnetic interference (EMI) and noise. Thinner gauge coil wire tends to give less dynamic range than thicker wire. However, these traits don't necessarily affect the “type” of pickup.
Many readers may be familiar with the distinction between single-coil and dual-coil (humbucker) pickups when speaking of magnetic pickups. Aside from a different visual appeal, these two variants deliver very contrasting returns in sound profile.
Dual-coil pickups (humbuckers) are designed that way in order to cancel out hum (hence the name “humbucker”). This is achieved by winding each coil in opposite directions. They accentuate the mid-range and low frequencies. Likewise, the notes sound much cleaner, at the expense of losing some of the upper harmonics one can find with single-coil pickups.
Related article: How Do Single-Coil Pickups (Guitar/Bass) Work?
Other coil designs include:
- P90 pickups: which are wider but shorter single coils that offer a rounder tone than the usual single-coil pickup.
- Split-coils: which are dual coils partially bound and which can be found mostly in precision basses. Their purpose is to enhance both high and low frequencies.
- Z-shape coils: which are “single-coil humbuckers” aimed at partially reducing hum without reducing the high-end content of the tone.
- Triple buckers: Fender's alternative humbucker consisting of three coils to boost gain, though they also have an effect on reducing the high-end.
To learn more about P90 pickups, check out my article What Are P90 Pickups & How Do They Work?
Preamps (Active Pickups Only)
Passive pickups work as simple transducers that generate electrical signals and carry them to the amplifier.
On the other hand, active pickups include a preamp module that filters noise and boosts the electric signals prior to reaching the output jack of the guitar.
The sound of active pickups is described as powerful and clean. The preamp's gain allows the pickup to wound fewer times, which helps reduce EMI.
Notwithstanding, some people may have issues with the lack of nuances in the sound as opposed to what you would get with passive pickups.
The printed circuit board (PCB) that hosts the preamplifier may also have its own tone-shaping designs through audio filters and general EQ.
For more information on passive and active pickups and general EQ, check out the following My New Microphone articles:
• Are Active Guitar Pickups Or Passive Guitar Pickups Better?
• Complete Guide To Audio Equalization & EQ Hardware/Software
When it comes to magnetic pickups, the magnets inserted in the pickup impact the tone, although the degree remains a topic of debate.
These magnets are mostly made of either ceramic or alnico, albeit there are also neodymium pickups to a lesser extent.
Ceramic pickups are known to produce a powerful razor-sharp tone, while alnico pickups endow the sound with a warmer and smoother envelope.
Neodymium magnets offer greater gain but are considered too powerful for guitars. Their usage on bass guitars (which have thicker, more inert strings) is limited as well.
To learn more about the different magnet types used in guitar and bass pickups, check out my article Ceramic Guitar Pickups Vs. Alnico Guitar Pickups.
There are also distinctions in relation to pickup covers and how different materials affect the sound. We can think of “covered” and “uncovered” pickups as their own types for the purposes of this section.
Contrasting plastic covers with metal covers (such as zinc, nickel, and chrome), the former makes virtually no difference in tone. In contrast, metal covers tend to encompass the vibrational energy and, therefore, the pickup renders a bit of a flatter response.
The level of contrast in sound between uncovered and covered pickups is still a hotly debated topic. Some even question whether the cover is the main culprit, pointing to height as the sole cause of the tonal shift.
For more information on pickup covers and their effects on tone, check out my article Do Guitar Pickup Covers Affect Tone?