PURPOSE: A model of vocal formants.
DESCRIPTION: This short tube is closed on one end and has a sliding reed inside it, so when it is inverted the reed slides from one end to the other. As the air passes through the reed it vibrates, producing a large number of harmonics. As the reed slides toward the closed end, the vibrating air column becomes longer, and vice versa. When the air column starts long and becomes shorter, the sound goes ah.......ooh. When the gizmo is inverted, as the tube becomes shorter the sound changes in reverse, going ooh......ah!!
REFERENCES: (PIRA unavailable.)
EQUIPMENT: Plastic tube with sliding vibrating reed.
SETUP TIME: None.
Go back to Lecture-Demonstration Home Page.