PURPOSE: To show the loudspeaker motion produced by waves of various shapes.

DESCRIPTION: Using waves of a few Hertz, the shape, amplitude and symmetry of the pulses can be observed by watching the movement of the speaker cone. The oscillator must have a reasonably large amplitude.

SUGGESTIONS: Video projection available for large halls.

REFERENCES: (PIRA unknown.)

EQUIPMENT: Wavetek oscillator and large speaker.

SETUP TIME: None.