The Great Stalacpipe Organ is an electrically actuated lithophone located in Luray Caverns, Virginia, USA. It is operated by a custom console that produces the tapping of ancient stalactites of varying sizes with solenoid-actuated rubber mallets in order to produce tones.

The instrument's name was derived from the resemblance of the selected thirty-seven naturally formed stalactites to the pipework of a traditional pipe organ along with its custom organ-style keyboard console. It was designed and implemented in 1956 over three years by Leland W. Sprinkle inside the Luray Caverns near Shenandoah National Park in Virginia, USA.

Sprinkle created the Great Stalacpipe Organ over three years by finding and shaving appropriate stalactites to produce specific notes. He then wired a mallet for each stalactite that is activated by pressing the correct key on the instrument's keyboard.

The organ console was constructed by Klann Organ Supply of Waynesboro, Virginia. The original console design featured volume-control switching cylinders actuated by pedals and ranks of draw-knobs designated "Pedal," "Harmonic," "Solo," and "Echo" which altered the amplifier settings, but this feature was subsequently removed in favor of the aesthetics offered by amplifying every note at a constant level. The organ can be heard throughout the caverns without use of the loudspeaker system, though it is not typically operated this way when open to the public.

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