A ribbon microphone is a type of dynamic microphone that uses a thin aluminum, duraluminum, or nanofilm ribbon placed between the poles of a magnet to generate voltages by electromagnetic induction. Ribbon microphones are typically bidirectional, meaning they pick up sounds equally well from either side of the microphone.
Ribbon microphones consist of a thin strip of metallic foil suspended in front of a magnetic plate. Sound waves cause the foil to vibrate, producing fluctuations in the electrical current, creating the audio signal.
This extremely sensitive configuration picks up a wide range of frequencies and produces an extraordinarily rich representation of the original sound. The trade off for this sensitivity is the delicacy of the mechanism. Ribbon microphones are also sensitive to physical impacts and therefore are not considered portable and can be easily damaged by power overdrive.
Ribbon microphones are not as commonly used as moving-coil microphones today. There are some modern manufacturers that currently make ribbon microphones, but they are primarily regarded as studio microphones.