Acoustic Guitar Pickup Systems: Piezo, Magnetic, and Mic

Why acoustic guitars need a pickup system

An acoustic guitar produces sound by amplifying string vibration through its body and soundhole. According to Martin's acoustic guitar type guide, body shapes like the Dreadnought deliver a loud, projective tone with strong bass, which works well in small settings. But on a stage with drums, electric instruments, or a loud audience, the natural sound may not carry enough.

A pickup system converts string or body vibration into an electrical signal that you can send to an amplifier or PA. It is the difference between being heard and being inaudible at a gig or open mic. If you plan to perform, a reliable pickup system is essential. For more on choosing an instrument, see our guide to best acoustic-electric guitars.

Piezo (undersaddle) pickups

Piezo pickups are the most common type in factory-installed acoustic-electric guitars. They use a thin piezoelectric sensor, often mounted beneath the saddle, that detects the mechanical pressure of the vibrating strings. The result is a clean, articulate tone that captures each string's attack and pitch separately.

Some players describe piezo tone as bright and slightly 'quacky', but modern systems include tone controls to shape the sound. For example, the Fishman Sonitone preamp mentioned in Martin's electronics guide includes a Tone control that can roll off treble for a warmer voice. Many piezo systems also feature a built-in chromatic tuner and a phase switch to help reduce feedback, as seen on the Fishman MX-T and other preamps.

If you need a straightforward, reliable system for live playing, piezo is a solid choice. Learn more about piezo pickups in acoustic-electric guitars.

Magnetic (soundhole) pickups

Magnetic pickups work like electric guitar pickups: they use magnets and coils to sense the vibrations of the metal strings. They are usually installed in the soundhole, so you can add them to a guitar that lacks built-in electronics without permanent modification.

Because magnetic pickups respond to string movement rather than the guitar body, they produce a warmer, rounder tone that can sound more like an electric guitar. They are less prone to feedback than microphone systems and work well in high-volume situations. However, they may not capture the 'air' and resonance of the actual guitar, so some players find them less acoustic-sounding.

If you play in a band and want something that cuts through without needing extra EQ, a magnetic pickup could be your choice. Compare different acoustic-electric setups in our best acoustic-electric guitars guide.

Microphone-based systems

Microphone pickups capture the actual sound of the guitar as it moves through the air, including the body's resonance and the room's ambience. They can deliver a natural, studio-quality tone that is hard to match with other pickups. Martin's electronics guide describes systems like the LR Baggs Anthem, which includes a small internal microphone (the Tru Mic) designed to pick up the instrument's true voice.

However, microphones are more susceptible to feedback, especially in loud stage environments. To control this, many microphone systems include a blend control that lets you mix the mic signal with a pickup, or a phase inversion switch to cancel out unwanted frequencies. The Fishman Aura VT Blend, for example, lets you seamlessly transition from an undersaddle pickup to 100% Aura HD for a mic'd studio sound.

Microphone systems are ideal for recording, singer-songwriter sessions, or any setting where you want the most natural reproduction. For tips on capturing your sound, see our recording guitar guide.

Control features that shape your tone

Modern pickup systems often include more than a simple volume control. Based on the preamps listed in Martin's electronics guide, you can find features like a Tone control to adjust bass and treble, a Phase switch to reverse polarity and reduce feedback, and a built-in chromatic tuner that mutes the output for silent tuning.

Some systems, such as the Fishman Aura VT Blend, add a Blend knob to mix between the undersaddle pickup and a microphone. The LR Baggs Anthem offers separate mic level control and a battery check. These controls let you fine-tune your sound for different venues and playing styles.

Understanding these features helps you choose a system that matches your needs. If you often play loud gigs, look for phase and feedback-reduction options. If you record frequently, consider blendable mic options. For more detail, check our article on acoustic guitar preamp controls.

How to choose the right system for you

Start by thinking about where you will use the guitar most. If you play live with a band, a piezo or magnetic system with feedback control may be more practical than a microphone. If you record at home or play in quiet settings, a microphone or blended system will give you a more natural sound.

Your personal tone preference also matters. Do you like the bright, punchy sound of a piezo, or the warm, round voice of a magnetic pickup? Do you want the full acoustics of a microphone? Many players choose a system that offers both a pickup and a microphone with a blend control, so they can dial in the exact mix.

For a new guitar, look for models with a built-in system that already matches these goals. Our best acoustic-electric guitars guide compares many options side by side. If you already own an acoustic guitar, you can always add a magnetic soundhole pickup or an aftermarket piezo system later.

Also remember to protect your hearing. The NIDCD warns that long exposure to sounds at or above 85 dBA can cause hearing loss. If you play loud gigs or rehearse with an amplifier, use volume controls or earplugs to keep levels safe. Learn more about gigging guitar guide.

• Live performer: Choose a piezo or magnetic system with phase control and a tuner.
• Studio recorder: Look for a microphone or hybrid system with blend control.
• Beginner: A simple piezo system with volume and tone is often enough.
• You want electric-style warmth: Consider a magnetic soundhole pickup.

What to pick for your use

Questions

What is the difference between piezo and magnetic pickups?

Piezo pickups sense string pressure through a crystal placed under the saddle, producing a bright, direct tone that emphasizes the acoustic nature. Magnetic pickups use magnets and coils to sense string movement, resulting in a warmer, rounder sound similar to an electric guitar. Each has its own character, so the choice depends on your tone preference.

Do I need a microphone pickup to get a natural sound?

Not necessarily. A good piezo or magnetic system can sound quite natural after equalization. A microphone pickup captures the guitar's body and room ambience, which some players prefer for recording. Many hybrid systems let you blend a pickup with a microphone for the best of both worlds.

Why does my acoustic-electric guitar feedback on stage?

Feedback happens when the amplified sound from speakers is picked up again by the guitar's body or pickup, creating a loop. To reduce feedback, you can use a phase switch to invert the signal, lower the volume, move away from speakers, or choose a pickup system with a dedicated feedback control.

Can I add a pickup to an existing acoustic guitar?

Yes. Soundhole magnetic pickups can be installed without any permanent modification. Undersaddle piezo pickups usually require a professional installation because they involve modifying the saddle and bridge. If you do not want a permanent change, a soundhole pickup is the simpler option.