PURPOSE: To demonstrate the relationship of musical pitch and musical intervals to mechanical vibration frequency.
DESCRIPTION: A set of four toothed wheels is mounted on a fast rotator, where the ratio of number of teeth on the four wheels is 4:5:6:8. Tones are produced by holding a piece of cardboard against the spinning teeth. The resulting notes are the harmonics 4, 5, 6, and 8 of the overtone series, which form a major triad with the octave. A second set of wheels contains a different set of tooth ratios and therefore creates a different chord.
SUGGESTIONS: Be careful! This can trim your fingernails REAL fast.
REFERENCES: (PIRA 3C20.40)
EQUIPMENT: Savart's Disk apparatus with two sets of toothed wheels.
SETUP TIME: None.
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