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What's the difference between magnetic and piezo pickups?
Two pickups asking two completely different questions. A magnetic pickup asks "how is this string's own vibration disturbing a magnetic field?" A piezo pickup asks "how much physical pressure is hitting this crystal right now?" Same job — turn string vibration into a signal — completely different physics.
Magnetic, briefly
The short version: a magnet's field gets disturbed by a vibrating steel string, and a coil of wire around the magnet turns that disturbance into signal. Steel is doing all the work, which is exactly why this only works on steel strings. For the full construction rundown — single-coils, humbuckers, and the rest of the family tree — see Pickups • What's the difference between single-coil and humbucker pickups?.
Piezo: pressure, not magnetism
A piezo pickup uses a crystal or ceramic element, usually sitting right under the saddle, that generates its own tiny voltage when it's physically squeezed or flexed. No magnet, no coil reading a field — it's just responding to mechanical pressure transmitted through the saddle every time a string moves. Because it's sensing physical motion instead of a magnetic disturbance, it doesn't care what the string is made of.
Why nylon strings need piezo, not magnetic
Nylon isn't magnetic. Full stop. A magnetic pickup under a nylon string has nothing to disturb its field, so it picks up essentially nothing — which is why every classical or flamenco acoustic-electric runs a piezo system instead. Not a design preference. It's the only option physics leaves on the table.
How they actually sound different
- Magnetic leans warmer and rounder, hums under the same electrical interference every single-coil deals with, and sounds like what most people mean by "electric guitar tone."
- Piezo leans bright, present, and a little percussive — it captures string attack and body resonance more directly, resists feedback well at stage volume, but can sound thin or quacky without a decent preamp smoothing it out.
- Some acoustic-electrics blend a piezo with an internal mic or a magnetic soundhole pickup specifically to soften that piezo edge.
Which one's actually in your guitar
Solid-body electrics run magnetic, full stop. Nylon-string classicals run piezo, full stop. Steel-string acoustics are the gray area — piezo under the saddle is the most common setup, sometimes paired with a mic or soundhole pickup for a rounder blend.
Taylor ES systems often have a humbucker embedded into the neck block. No joke! But it acts like a single coil. Only one coil has output, the other is just there to eat noise.
Not sure which one's in your guitar, or thinking about adding a pickup to an acoustic that doesn't have one? Book Now for a free evaluation.