The most common types of microphones are dynamic and condenser. Both use a transducer to convert sound energy into electrical energy. This electrical energy is usually recorded or transmitted over a loudspeaker.
A dynamic microphone creates sound using electromagnetic induction. Conversely, condenser microphones operate using an electrostatic principle. Dynamic microphones tend to be more rugged, while condenser microphones can be fragile.
Condenser microphones also require an additional power source called phantom power. This is usually provided by a battery, an external power supply, or by the mixing board. A dynamic microphone does not need phantom power.
A dynamic microphone is typically either a moving coil or a ribbon microphone. In a moving coil setup, the coil — called a voice coil — is suspended within a magnetic field. When sound waves hit the diaphragm inside the microphone, this coil moves and enters the magnetic field, and an electrical signal of the sound is created.
A ribbon microphone uses a very thin aluminum ribbon diaphragm suspended in the magnetic field. Similar to a moving coil microphone, sound waves cause the ribbon to move into the magnetic field, which converts sound into electrical signals. Moving coil dynamic microphones are used more often, since ribbon microphones are more delicate.
The condenser microphone uses two plates, one movable and one fixed. These two plates create a capacitor, or condenser. The capacitor is charged by the power supply. Sound waves cause the movable plate to fluctuate, creating an electrostatic charge which changes the voltage between the plates.
A condenser microphone is usually more fragile and expensive than a dynamic microphone. As a result, condenser microphones are used most often in a controlled studio environment. Dynamic microphones are well-suited for both studio and live performance use.
Dynamic microphones produce a small output signal, which typically requires a lot of amplification. This works well for picking up sounds that are close to the microphone. Using a dynamic microphone may be challenging when trying to pick up soft or distant sounds. These sounds generally require a lot of amplification that can create noise in the sound signal. A condenser microphone will be more successful in picking up these ambient sounds without adding extra noise.
Both dynamic and condenser microphones can pick up different frequencies and have various directional responses. Using microphones that pick up varied frequencies can help separate recorded sounds, such as those from different instruments in the room or on a stage. The directional response, or the angle from which the microphone will pick up signals, can also help isolate sounds.