Piezo vs Magnetic Acoustic Pickups: What to Know

What each pickup senses

A piezo under-saddle pickup sits beneath the saddle and converts the mechanical vibration of the saddle into an electrical signal. Because the saddle transfers string vibration into the top, the pickup hears part of the body's response along with the string. The string is the first point of contact, and its vibration is shaped by the guitar's tonewoods, body size, bracing, and construction. Many factory acoustic-electric guitars use under-saddle piezo systems because they are compact, reliable, and work with both steel and nylon strings.

A magnetic soundhole pickup mounts in or over the soundhole and senses the movement of steel strings through magnets and coils. It does not depend on the guitar body the same way, so the same magnetic pickup tends to sound more alike across different guitars. For a closer comparison of the two mounting styles, see under-saddle versus soundhole pickups.

Tone: piezo versus magnetic

Under-saddle piezo pickups typically sound bright, present, and percussive. They preserve the attack of the pick or fingers and can sound very acoustic-like through a PA, although some players find the strongest high end quacky until they shape it with EQ. The top has a large influence here: it responds directly to the strings through the bridge and shapes volume, attack, dynamic range, and tonal balance.

Magnetic soundhole pickups sound warmer, rounder, and more electric-like because they mainly hear the string, not the body. That makes them useful for blues, jazz, country, or plugged-in rock, but they can hide the wooden resonance that makes an acoustic guitar sound like itself. If you want to compare them with other acoustic pickup types, see guitar pickup configurations.

Feedback and stage volume

Feedback is one of the main reasons stage players choose piezo under-saddle systems. A phase switch on the preamp can be especially helpful: reversing the phase 180 degrees can decrease feedback and increase bass response. When you shop for a stage guitar, look for an acoustic-electric with a phase switch or a built-in tuner that mutes the output while you tune.

A magnetic soundhole pickup can work for quieter gigs and recording, but it may need more careful EQ and monitor placement at higher stage volume. If feedback starts, turn down the monitor, move away from the speaker, and reduce gain before changing the pickup. The acoustic-electric feedback article walks through common causes and fixes.

Amplified shows can be loud. The National Institute on Deafness and Other Communication Disorders notes that long or repeated exposure to sounds at or above 85 dBA can cause hearing loss, so wear earplugs when you rehearse or perform.

Preamp controls matter

A piezo pickup usually sounds best through a preamp. Most current acoustic-electric systems include volume and tone controls; some add a phase switch and a built-in chromatic tuner. The tone control lets you reduce treble, and the phase switch can suppress feedback at high volume. See acoustic guitar preamp controls for a fuller look at the controls you will see on an acoustic-electric.

Some systems go beyond a single pickup. The Fishman Aura VT Blend, for example, blends an undersaddle pickup with a processed mic'd sound for a more studio-like voice. The LR Baggs Anthem combines a pickup with an internal microphone and includes mix and phase controls. If you record often, a blend system can sound closer to a miked acoustic guitar than a plain under-saddle pickup.

Which pickup should you choose?

Start with the music you play. If you mostly play fingerstyle, record at home, or want the amplified sound to match the unplugged guitar, choose a piezo under-saddle system. Look for an acoustic-electric guitar with a solid top and an onboard preamp with tone and phase controls.

If you play blues, jazz, or plugged-in rock where a warm, electric-style voice works better, a magnetic soundhole pickup may feel more natural. You can add one to almost any steel-string acoustic guitar without permanent changes, making it a simple way to amplify an existing instrument.

If you already own a solid-top acoustic guitar and want a low-commitment upgrade, a soundhole pickup is often the easiest route. If you are buying your first amplified acoustic, an acoustic-electric with an under-saddle piezo system is the more common all-round solution.

What to pick for your use

Questions

Can a magnetic soundhole pickup work on a nylon-string guitar?

No. Magnetic pickups sense steel strings, so nylon strings will not produce a usable signal. A piezo under-saddle pickup works with both steel and nylon strings, which is why classical and crossover guitars usually use piezo systems. For more background, see piezo pickups for acoustic-electric.

Why does my piezo pickup sound quacky?

The bright, percussive attack is a normal trait of under-saddle pickups. You can reduce it with the tone control on your preamp, or choose a system that blends the undersaddle pickup with a microphone or processed acoustic signal.

Do I need a preamp for a magnetic soundhole pickup?

Some magnetic pickups are passive and can plug directly into an amp, but a preamp gives you more control over tone and level. For a piezo pickup, a preamp is strongly recommended because it matches the impedance of the pickup to the amp or mixer.

Which pickup type is better for live gigs?

For loud stage work, a piezo under-saddle system with a phase switch is usually the more dependable choice. The phase switch can suppress feedback at high volume. A magnetic soundhole pickup can work live, but you may need to pay more attention to EQ and monitor placement.

Can I add a piezo pickup to a guitar I already own?

Yes, but it usually requires replacing the saddle and adding a preamp or output jack, so it is more involved than a soundhole pickup. If you want a simple, removable option, a magnetic soundhole pickup is easier to install yourself.