All microphones have a diaphragm, which is like a sail that detects changes in air pressure. Our eardrums work similarly to a microphone’s diaphragm. In a dynamic microphone, a heavy voice coil is attached to the diaphragm. When the diaphragm moves back and forth, the voice coil moves around a magnet. This movement creates an electrical current through electromagnetic induction, which is the process where moving a coil in a magnetic field generates electricity. Dynamic microphones have a large voice coil, adding inertia and making it difficult to hear the quietest sounds. However, this characteristic also makes them good at isolating sound sources, which is useful in loud environments or for close-miking instruments.