Simple Explanation

The part of a speaker that uses magnets to move the cone and make sound.

Concise Technical Definition

The assembly in a loudspeaker that includes the magnet, voice coil, and pole pieces, which together generate the force needed to move the diaphragm and produce sound.

Layman-Friendly Analogy

Like the engine in a car—it powers the motion that makes everything work.

Industry Usage Summary

The motor structure is critical to a speaker’s performance, affecting sensitivity, control, and distortion. High-end designs may use advanced materials or features like shorting rings to reduce non-linear behavior.

Engineering Shortcut

Magnetic + coil system that drives cone motion.

Full Technical Explanation

In loudspeaker design, the motor refers to the complete assembly that drives the movement of the diaphragm or cone. It typically consists of a permanent magnet, a voice coil, and metal pole components (top plate, pole piece, and back plate). When current flows through the voice coil, it interacts with the magnetic field in the gap, producing a force (via the Lorentz force law) that moves the diaphragm. The motor's design—magnet strength, gap geometry, coil construction—has a direct impact on sensitivity, linearity, power handling, and distortion. Well-designed motors may include features like shorting rings, venting, or dual-gap structures to improve efficiency and reduce thermal or inductive distortion.