Harmonium

harmonium: see reed organ.

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harmonium

 or reed organ

Harmonium by Jacob Alexandre, Paris, 19th century

(credit: Behr Photography)

Free-reed keyboard instrument in which wind from a foot-operated bellows causes metal reeds to vibrate. Pitch is determined by the size of the reed; there are no pipes. Separate sets of reed produce different tone colours, the sound quality being determined by the size and shape of the tone chamber surrounding each reed. The harmonium developed in the early to mid-19th century in Europe and America, and it was a very popular church and home instrument into the 1930s.

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harmonium

a musical keyboard instrument of the reed organ family, in which air from pedal-operated bellows causes the reeds to vibrate

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Harmonium 

a keyboard wind instrument. The harmonium was invented in the second decade of the 19th century; its precursor was the orgue expressif designed by the Frenchman G. J. Grenié in 1810. A similarly constructed instrument was created in 1818 by the master A. Häckel. The modern harmonium resembles a small upright piano; it has a piano keyboard, with six to 20 registers activated by movable levers. The keyboard is divided into a left side, with a range from C two octaves below the bass staff to E at the bottom of the treble staff, and a right side, with a range from F at the bottom of the treble staff to C two octaves above the treble staff. Sound is produced when air passes over steel tongues set in brass frames, causing the tongues, which act as free reeds, to vibrate. Air is pumped through channels to the reed compartments by pedal-operated bellows. The sound of the harmonium is similar to that of the organ.