PURPOSE: To demonstrate the formant structure of different vocal sounds.

DESCRIPTION: The microphone signal is input into a TDS scope with a spectrum analyzer board, and the scope displays both the wave shape and spectrum of the input wave.

Differences in the formant structure are easily observed for various vowel sounds such as (upper left to lower right) "oo," "aw," "ah," "eh," "i," and "ee." Click here to hear the sound and see the wave shape and spectrum for a male voice singing these sounds successively at a frequency of about 100 Hz.

To illustrate that the nasal "ee" formant (about 2500 Hz) does not change as the frequency of the sung note is changed by over one octave (for a male voice from about 100 Hz to 200 Hz), click here. The wave shape and spectrum for an "ee" sound at 100 Hz and 200 Hz are shown below.

SUGGESTIONS: Practice before doing this one.

REFERENCES: (PIRA unknown.) See Demonstration Reference File for manual and other information.

EQUIPMENT: PC 486 with sound blaster card and real time audio spectrograph card.

SETUP TIME: 5 min.