This Is How Acoustic Guitar Pickups Work


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Playing an acoustic guitar is fun and rewarding by yourself, but recording and performing can be challenging. Some acoustic guitars have pickups built into them, but otherwise, you may need to modify your instrument to add one. It helps to know what kinds of pickups will work for an acoustic guitar — and how they work — in these instances.

Acoustic guitar pickups work by converting the strings’ vibrations into electronic signals to be transmitted into the amp, the same way electric guitars do. Acoustics can have piezoelectric or magnetic pickups built-in or installed, or you can fit them with a microphone that will work as a pickup.

In this article, we will identify the different kinds of acoustic guitar pickups and explain how they work to amplify your music. The next time you need to boost or record your acoustic playing, you’ll be prepared to plug in and be easily heard.

Piezoelectric Pickups

Rather than using a conventional magnetic pickup system to amplify their acoustic, some players opt to use piezoelectric or “piezo” pickups instead. These are also known as contact microphones, occasionally already installed under the bridge of an acoustic guitar.

How Piezo Pickups Work With Acoustic Guitars

This type of pickup consists of piezo crystals, which accumulate a changing electrical charge as the strings and body vibrate when pressed to an instrument. This charge is then converted directly into a current and picked up by a sound system or amp.

Piezos can lead to a “tinny” sound since the crystals have a higher output impedance (caused by a drop in voltage from the resistance to the current). However, some guitarists find the piezo pickups to be more “natural” sounding, as they capture both the vibrations of the strings and the warm, resonating sound of the guitar’s chamber. 

How To Fix the “Tinny” Sound Caused By Piezos

Some musicians deal with the “tinny” sound of piezo pickups by using a preamp pedal. A preamp essentially takes a weak electrical signal and strengthens it to send through to a loudspeaker. Most guitar amps already have an equipped preamp, but using an extra pedal can help make your acoustic playing clearer. 

The FLAMMA FS06 Digital Preamp Pedal has seven different preamp models and can connect directly to a PA system. Not only can it help your acoustic sound better, but it’s also useful for an electric guitar!

How To Attach a Piezo Pickup

Piezo pickups can be mounted to the guitar’s bridge or attached to the body with a gentle adhesive. Make sure to attach the pickup as close to the strings as possible without interfering with playing. This Randon Acoustic Guitar Piezo Pickup features a reliable adhesive that won’t damage the finish of your instrument.

To mount a piezo to your acoustic guitar:

  1. Figure out where you want the pickup to go.
  2. Press the adhesive side onto the body of your guitar for approximately 30 seconds.
  3. Make sure the pickup is secure.
  4. Plug it into your preamp system and turn it on.
  5. Adjust the sound and play!

Magnetic Pickups

Electric guitars are typically fitted with magnetic pickups, but there are ways to make them work for acoustics, too!

How Magnetic Pickups Work With Acoustic Guitars

Magnetic pickups are made of permanent magnets wrapped tightly in a copper wire coil, usually one under each string. The pickups magnetize the strings and create a magnetic field that vibrates as you pluck the strings. The magnetization creates a current in the copper coil, amplifying the sound when the guitar is plugged into an amp or loudspeaker.

Magnetic pickups tend to sound less natural than piezo pickups, and they also don’t work with nylon strings. However, they pick up much more sound than piezos do, and it’s easy to mimic an electric guitar sound with them. The AMUMU SP30 Magnetic Soundhole Pickup will fit most acoustic sizes and comes in a wood finish to match an acoustic guitar’s look.

Drawbacks of Magnetic Pickups

Magnetic pickups rely on the strings’ magnetic properties to work, so they fail to pick up certain vibrations that make acoustic guitars sound unique. This includes the chamber’s echo, which gives it a warm tone, and the percussive sounds from a hand hitting the instrument.

Thus, magnetic pickups tend to sound less natural and can have an “electric” quality. They are, however, more powerful and reliable than piezos. Musicians can remedy this by using both magnetic and piezo pickups, but some players may find that too cumbersome to install.

You’ll have to decide what you prefer your pickup to have depending on how you play and how you want to sound. You may like magnetic pickups for some songs and piezo pickups for others!

How To Attach a Magnetic Pickup to an Acoustic Guitar

Since magnetic pickups need to reach far enough to pick up vibrations from every string, the best place for a pickup is usually in the soundhole.

To place this type of pickup in your guitar:

  1. Loosen all the strings enough so that you can pinch them all together.
  2. As you pinch the strings, gently lift them up and insert the pickup into the soundhole.
  3. Fit the pickup snugly at the top of the hole, near the fretboard.
  4. Tighten the strings and re-tune the guitar. 
  5. Plug it in and play!

Internal Condenser Microphones

Perhaps the simplest way to amplify your acoustic guitar is an internal condenser microphone. Though these aren’t pickups in the traditional sense, some guitarists find that this method gets players as close to a natural sound as an acoustic guitar can be.

How Condenser Mics Work

Condenser mics use charged metal plates to pick up vibrations from the strings. The voltage changes as the plates move up and down, translating the vibrations into sound.

Condenser mics work differently from dynamic mics, which are typically useful onstage and for performances. Dynamic mics work with a small induction coil and magnet to create electromagnetic induction. However, they work better with vocals and electric guitars

How To Attach an Internal Condenser Mic to an Acoustic Guitar

If you just need to record your playing, you can simply set a mic in front of your guitar. Just be sure not to move around too much and to stay centered in front of the microphone!

However, condenser mics can also be clipped to the inside of the hollow body of a guitar. This can be useful for people who will move around when they play. The HEIMU Clip-On Condenser Microphone can be clipped onto your guitar’s soundhole easily and comes with an adaptor that will allow you to connect with various wireless systems.

To attach an internal condenser mic to your acoustic:

  1. Clip the mic to the soundhole, taking care to avoid touching it to the strings.
  2. Make sure you aren’t hitting the mic with your hand.
  3. Plug the mic into a sound system.
  4. Go ahead and play!

Final Thoughts

Acoustic guitar pickups work in much the same way that electric pickups do: picking up the strings’ vibrations and turning them into an electrical signal, which can then be recorded or plugged into an amplifier. Guitarists can fit acoustics with piezo pickups, magnetic pickups, or traditional condenser microphones. 

If you’d like to put a pickup on your acoustic guitar, knowing how the different types of pickups work can help you decide what will best work for you. With these tips, you should be able to determine the best kind of pickup for your acoustic guitar.

David Sandy

Hey there! My name is David Sandy and I'm the founder of Sandy Music Lab. I've been playing guitar for several years now and created this site to be able to share and explore music with others. Check out my recommended guitar gear!

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