Hyperbass flute
The hyperbass flute is the largest and lowest pitched instrument in the flute family, with tubing reaching over 15 metres in length. It is pitched in C, four octaves below the concert flute (three octaves below the bass flute, two octaves below the contrabass flute, and one octave below the double contrabass flute), with its lowest note being C0, one octave below the lowest C on a standard piano. At 16 Hz, this is below what is generally considered the range of human hearing (20 to 20,000 Hz).