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Octobass
There are only seven known examples of this rare string instrument in the world.
Invented in 1850 by Jean-Baptiste Vuillaume, the octobass was intended to bring an extremely deep rumble to the orchestra sound. The three-stringed instrument stands between 11 and 12 feet tall, about twice the height of a double bass. This giant bass produces sound so low, some of the notes fall outside the range of human hearing—these vibrations can only be felt.
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