Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, radio and television broadcasting, and in computers for recording voice, speech recognition, VoIP, and for non-acoustic purposes such as ultrasonic sensors or knock sensors.

A public address system (PA system) is an electronic system comprising microphones, amplifiers, loudspeakers, and related equipment.

Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, radio and television broadcasting, and in computers for recording voice, speech recognition, VoIP, and for non-acoustic purposes such as ultrasonic sensors or knock sensors.

Audio engineers work on the "...technical aspect of recording—the placing of microphones, pre-amp knobs, the setting of levels. The physical recording of any project is done by an engineer ... the nuts and bolts."

Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, radio and television broadcasting, and in computers for recording voice, speech recognition, VoIP, and for non-acoustic purposes such as ultrasonic sensors or knock sensors.

The essential elements of a telephone are a microphone (transmitter) to speak into and an earphone (receiver) which reproduces the voice in a distant location.

This was independently developed by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. Although Edison was awarded the first patent (after a long legal dispute) in mid-1877, Hughes had demonstrated his working device in front of many witnesses some years earlier, and most historians credit him with its invention.

David Edward Hughes (16 May 1831 – 22 January 1900), was a British-American inventor, practical experimenter, and professor of music known for his work on the printing telegraph and the microphone.

The first microphone that enabled proper voice telephony was the (loose-contact) carbon microphone.

The carbon microphone, also known as carbon button microphone, button microphone, or carbon transmitter, is a type of microphone, a transducer that converts sound to an electrical audio signal.

A microphone, colloquially nicknamed mic or mike, is a transducer that converts sound into an electrical signal.

For example, a microphone converts an acoustic signal to a voltage waveform, and a speaker does the reverse.

Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, radio and television broadcasting, and in computers for recording voice, speech recognition, VoIP, and for non-acoustic purposes such as ultrasonic sensors or knock sensors.

A radio communication system requires a transmitter and a receiver, each having an antenna and appropriate terminal equipment such as a microphone at the transmitter and a loudspeaker at the receiver in the case of a voice-communication system.

Also in 1923, the ribbon microphone was introduced, another electromagnetic type, believed to have been developed by Harry F. Olson, who essentially reverse-engineered a ribbon speaker.

A ribbon microphone, also known as a ribbon velocity microphone, is a type of microphone that uses a thin aluminum, duraluminum or nanofilm of electrically conductive ribbon placed between the poles of a magnet to produce a voltage by electromagnetic induction.

A wireless microphone contains a radio transmitter.

A wireless microphone is a microphone without a physical cable connecting it directly to the sound recording or amplifying equipment with which it is associated.

The most common are the dynamic microphone, which uses a coil of wire suspended in a magnetic field; the condenser microphone, which uses the vibrating diaphragm as a capacitor plate, and the piezoelectric microphone, which uses a crystal of piezoelectric material.

The varying air pressure of sound waves imparts mechanical vibrations to the diaphragm which can then be converted to some other type of signal; examples of this type of diaphragm are found in microphones and the human eardrum.

Electro-Voice responded with their Academy Award-winning shotgun microphone in 1963.

Electro-Voice (commonly referred to as EV) is an American manufacturer of audio equipment, including microphones, amplifiers, and loudspeakers, focused on pro audio applications such as sound reinforcement and consumer electronics such as car audio.

Microphones typically need to be connected to a preamplifier before the signal can be recorded or reproduced.

They are typically used to amplify signals from analog sensors such as microphones and pickups.

During the second half of 20th century development advanced quickly with the Shure Brothers bringing out the SM58 and SM57.

The company became a consumer and professional audio-electronics manufacturer of microphones, wireless microphone systems, phonograph cartridges, discussion systems, mixers, and digital signal processing.

It is also possible to vary the pattern continuously with some microphones, for example, the Røde NT2000 or CAD M179.

RØDE Microphones LLC is an Australian-based designer and manufacturer of microphones, related accessories and audio software.

During the second half of 20th century development advanced quickly with the Shure Brothers bringing out the SM58 and SM57.

The Shure SM57 is a low-impedance, cardioid, dynamic microphone made by Shure Incorporated and commonly used in live sound reinforcement and studio recording.

A valve microphone is a condenser microphone that uses a vacuum tube (valve) amplifier.

A valve microphone is a condenser microphone which uses a valve amplifier rather than a transistor circuit.

This preamplifier is frequently phantom powered in sound reinforcement and studio applications.

A sound reinforcement system is the combination of microphones, signal processors, amplifiers, and loudspeakers in enclosures all controlled by a mixing console that makes live or pre-recorded sounds louder and may also distribute those sounds to a larger or more distant audience.

During the second half of 20th century development advanced quickly with the Shure Brothers bringing out the SM58 and SM57.

The Shure SM58 is a professional cardioid dynamic microphone, commonly used in live vocal applications.

A microphone, colloquially nicknamed mic or mike, is a transducer that converts sound into an electrical signal.

They generally produce a high-quality audio signal and are now the popular choice in laboratory and recording studio applications.

The typical recording studio consists of a room called the "studio" or "live room" (and sometimes additional isolation booths) equipped with microphones and mic stands, where instrumentalists and vocalists perform; and the "control room", where sound engineers, sometimes with record producers, as well, operate professional audio mixing consoles, effects units, or computers (post 1980s and 1990s) with specialized software suites to mix, manipulate (e.g., by adjusting the equalization and adding effects) and route the sound for analogue recording (on tape) or digital recording on hard disc.

Dynamic microphones use the same dynamic principle as in a loudspeaker, only reversed.

The dynamic speaker operates on the same basic principle as a dynamic microphone, but in reverse, to produce sound from an electrical signal.

This preamplifier is frequently phantom powered in sound reinforcement and studio applications. They require a power source, provided either via microphone inputs on equipment as phantom power or from a small battery.

Phantom power, in the context of professional audio equipment, is DC electric power transmitted through microphone cables to operate microphones that contain active electronic circuitry.

The Sennheiser "MKH" series of microphones use the RF biasing technique.

Sennheiser electronic GmbH & Co. KG is a German privately held audio company specializing in the design and production of a wide range of high fidelity products, including microphones, headphones, telephone accessories and aviation headsets for personal, professional and business applications.

They are used in many applications, from high-quality recording and lavalier use to built-in microphones in small sound recording devices and telephones.

A lavalier microphone or lavalier (also known as a lav, lapel mic, clip mic, body mic, collar mic, neck mic or personal mic) is a small microphone used for television, theatre, and public speaking applications in order to allow for hands-free operation.

There are two types, depending on the method of extracting the audio signal from the transducer: DC-biased microphones, and radio frequency (RF) or high frequency (HF) condenser microphones.

Audio signals may be synthesized directly, or may originate at a transducer such as a microphone, musical instrument pickup, phonograph cartridge, or tape head.