Loudspeaker

A loudspeaker (or loud-speaker or speaker) is an electroacoustic transducer; a device which converts an electrical audio signal into a corresponding sound. The first primitive loudspeakers were invented during the development of telephone systems in the late 1800s, but electronic amplification by vacuum tube beginning around 1912 made loudspeakers truly practical. By the 1920s they were used in radios, phonographs, public address systems and theatre sound systems for talking motion pictures.

The most widely used type of speaker today is the dynamic speaker, invented in 1925 by Edward W. Kellogg and Chester W. Rice. The dynamic speaker operates on the same basic principle as a dynamic microphone, but in reverse, to produce sound from an electrical signal. When an alternating current electrical audio signal is applied to its voice coil, a coil of wire suspended in a circular gap between the poles of a permanent magnet, the coil is forced to move rapidly back and forth due to Faraday's law of induction, which causes a diaphragm (usually conically shaped) attached to the coil to move back and forth, pushing on the air to create sound waves. Besides this most common method, there are several alternative technologies that can be used to convert an electrical signal into sound. The sound source (e.g., a sound recording or a microphone) must be amplified with an amplifier before the signal is sent to the speaker.

Loudspeaker (film)

Loudspeaker is a 2009 Malayalam film produced, written, and directed by Jayaraj, starring Mammootty, Sasi Kumar, Gracy Singh, Jagathy Sreekumar, Cochin Hanifa, Saleem Kumar, and KPAC Lalitha.

Plot

The movie is all about the relationships between two rare bred men from extremely different strata of society, but more in common than is apparent from the first look. They might have never run into each other, with their stark contrast in nature and life styles and would have hardly given each other a second look, if they hadn't met in these defined circumstances. But the movie throws them together, intertwined in worst of their days and progressively built in the rapport between the extremes, and infuses the spirit of worthy and meaningful life to all in the screen and those who watches them on screen.

Mammootty plays the lead role Mike Philippose, a barefooted uneducated simpleton who lands in the city, armoured with his loud voice, opinions and dazzling wit to stand up with the different level of etiquette's he find in the flats of the city. His arrival is as a kidney donor to ailing Anand Menon, an astrophysicist who returned to his home nation after working in US for the last forty six years. A dejected man who wants to run away from his memories, Menon is turned into the reverse track by Mike, who lives with his memories and snobs about his deceased father and about the silent hamlet of Thopramkudy.

Loudspeaker (disambiguation)

Loudspeaker may refer to: