A dynamic microphone uses electromagnetic induction — a coil moving in a magnetic field generates voltage

A dynamic microphone converts acoustic pressure to electrical signal via electromagnetic induction. A thin diaphragm is coupled to a coil of wire (the voice coil) suspended within a permanent magnet’s gap. When sound pressure moves the diaphragm, the attached coil moves through the magnetic field, inducing a voltage proportional to coil velocity. Advantages: robust construction (no power supply needed), handles high SPL without damage, reliable in harsh environments. The dynamic mic’s mass (diaphragm + coil) limits high-frequency and transient response compared to capacitor designs. Dynamic mics are the dominant choice for live sound reinforcement microphones.

Examples

A Shure SM58 is a dynamic microphone used on virtually every live vocal mic stand. Its mass and coil design mean it is less sensitive to very high frequencies (above 12 kHz) than a condenser mic, but it is robust and rejects handling noise.

Assessment

A dynamic mic and a condenser mic are both placed on a drum kit. Predict which will handle the high-SPL kick drum better and why. Predict which will capture cymbal overtones better and why.