Purpose:Determine the Fourier spectrum of various steady-state spoken and sung vocal (vowel) sounds.
Description:An amplified microphone is fed into a digitizing oscilloscope with an FFT function. The wave shape and spectrum are displayed on screen.
Consider inviting students with different voices up to try it out, and show how the vocal formants appear at different intonations. Compare the underlying structure to show how speech remains understandable even as formants shift.