Microphone

A Microphone is a device that converts sound into an electrical signal. 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. They are also used in computers for recording voice, speech recognition, VoIP, and for non-acoustic purposes such as ultrasonic sensors or knock sensors.

Types of Microphones

There are several types of microphones including Dynamic, Condenser, Ribbon, Carbon, Piezoelectric, Fiber Optic, Laser, Liquid, MEMS, and Hot Wire.

History

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

Microphone Polar Patterns

Microphones can be classified by their Polar Pattern. This refers to the microphone's directionality or pickup pattern. The most common types are Cardioid, Omnidirectional, Figure-8, Supercardioid, Hypercardioid, and Shotgun.

See Also

• Sound Recording
• Audio Engineering
• Broadcasting

External Links

• Britannica - Microphone

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  Shure mikrofon 55S
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  David Edward Hughes
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  Bogart Bacall AFRS
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  Oktava319 internal
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  Condenser microphone
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  AKG C451B
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  US Patent 3118022 - Gerhard M. Sessler James E. West - Bell labs - electroacustic transducer - foil electret condenser microphone 1962 1964 - pages 1-3
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  Patti Smith performing in Finland, 2007
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  Tauchspulenmikrofon
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  Edmund Lowe
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  Western Electric double button carbon microphone
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  Astatic crystal mic