Microphone types and characteristics

History of the microphone:

The history of the microphone begins with Sir Charles Wheatstone in 1827; he was the first person to use the word microphone but was not the one to invent it. 49 years later a person called Emile Berliner was the first person to invent the microphone, which was used as a voice transmitter, which was later known (and known to us now) as a telephone. Emile was not the one to invent the telephone but improved it with the microphone. 2 years later in 1878; David Edward Hughes invented the carbon microphone which was later then developed during the 1920s. With the invention of the radio, new broadcasting microphones were then also invented.

How a microphone works:

1. When you speak, sound waves are created by your voice which are then carried towards the microphone

2. Inside the microphone, the diaphragm moves back and forth as the sound waves hit it.

3. The coil, attached to the diaphragm, moves back and forth as well.

4. The permanent magnet produces a magnetic field that cuts through the coil. As the coil moves back and forth through the magnetic field, an electric current flows through it.

5. The electric current flows out from the microphone to an amplifier or sound recording device.

This is an image of Emile Berliner; the inventor of the first microphone.

Types of microphones:

- Dynamic

"Dynamic microphones are useful when the sound source is close and reasonably loud."

Dynamic microphones are great when you want to capture sound which is loud and close (as seen in the quote above from Sound On Sound website) also where the sound is predominantly bass or mid-range.. They also have the benefit of being tough and relatively inexpensive, and they don't require phantom power or batteries.

- Capacitor

"The majority of variable-pattern microphones are built around a dual-diaphragm design..."

Capacitor microphones are great at responding to very high audio frequencies, and are usually a lot more sensitive than their dynamic counterparts. Put it simply they require less amplification than dynamic models to produce the same output level from the same signal source, making them more suitable for quieter or distant sound sources.

- Electret condenser

Electret condensers are a stable dielectric material with a permanently embedded static electric charge; it is a type of condenser microphone, which eliminates the need for a polarizing power supply by using a permanently charged material.

- Ribbon

A ribbon microphone is a type of microphone that uses a thin aluminium, duralumin or Nano film 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.

- Carbon

The carbon microphone, also known as a carbon buttons microphone (or sometimes just a button microphone) or a carbon transmitter, is a sound-to-electrical signal transducer consisting of two metal plates separated by granules of carbon.

- Crystal

The crystal microphone uses a thin strip of piezoelectric material attached to a diaphragm. The two sides of the crystal take on opposite charges when the crystal is deflected by the diaphragm. The charges are proportional to the amount of deformation and disappear when the stress on the crystal disappears.

- Lavalier

It provides excellent yet background sounds will not be heard. It is designed best for 'talking heads'; lecturers, TV performers, interviewers or interviewees. Designed for clip-on lavalier and musical instrument use, it features an integral 80 Hz high-pass filter that provides easy switching from a flat frequency response to a low-end roll-off.

- Rifle

Rifle is a capacitor microphone suitable for video and audio recordings and transmissions where direct close-talking microphone applications are impossible; has excellent sound rejection from the side and the rear.

- Boom

A boom microphone is a directional microphone attached to a pole or arm. It’s mainly used in film and television, a boom microphone frees the hands of actors or reporters while allowing them to enjoy the amplified audio of a traditional microphone. Boom microphones can also be used to amplify a group conversation, as it can be positioned so that everyone's voice can be heard.

- Radio

A wireless microphone, Also known as a radio microphone, it has a small, battery-powered radio transmitter in the microphone body, which transmits the audio signal from the microphone by radio waves to a nearby receiver unit, which recovers the audio.