Electronic organ

An electronic organ is an electronic keyboard instrument which was derived from the harmonium, pipe organ and theatre organ. Originally, it was designed to imitate the sound of pipe organs, theatre organs, band sounds, or orchestral sounds. Today, it has developed into three or more types of instruments:

The immediate predecessor of the electronic organ was the harmonium, or reed organ, an instrument that was very popular in homes and small churches in the late 19th and early 20th centuries. In a fashion not totally unlike that of pipe organs, reed organs generated sound by forcing air over a set of reeds by means of a bellows, usually operated by constantly pumping a set of pedals. While reed organs had limited tonal quality, they were small, inexpensive, self-powered, and self-contained. The reed organ was thus able to bring an organlike sound to venues that were incapable of housing or affording pipe organs. This concept was to play an important role in the development of the electric organ.

In the 1930s, several manufacturers developed electronic organs designed to imitate the function and sound of pipe organs. At the time, some manufacturers thought that emulation of the pipe organ was the most promising route to take in the development of an electronic organ. Not all agreed, however. Various types of electronic organs have been brought to market over the years, with some establishing solid reputations in their own niche markets.

Electricity arrived on the organ scene in the first decades of the 20th century, but it was slow to have a major impact. Electrically powered reed organs appeared during the first decades of electricity, but their tonal qualities remained much the same as the older, foot-pumped models.

Thaddeus Cahill's gargantuan and controversial instrument, the Telharmonium, which began piping music to New York City establishments over the telephone system in 1897, predated the advent of electronics, yet was the first instrument to demonstrate the use of the combination of many different pure electrical waveforms to synthesize real-world instrument sounds. Cahill's techniques were later used by Laurens Hammond in his organ design, and the 200-ton Telharmonium served as the world's first demonstration of electrically produced music on a grand scale.

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