Sound & Hearing

Two Ways to Look at Sound

At Two Ways to Look at Sound you can play notes or collections of notes on a keyboard and analyze them in two ways. An oscilloscope shows the vibration pattern as a function of time on an upper screen, and a frequency analyzer shows the component frequencies on a lower screen. The keyboard is attached to a synthesizer which can play the sounds of many different instruments from flutes through guitars to horns. In addition, you may use a microphone and a sampler to record, play back and analyze, in either of the two ways above, the sound of your own voice or other sounds.

This exhibit shows why you can tell the difference between two instruments even though they are playing the same frequency note. In essence different instruments play different amplitudes of overtones, musicians say that the timbre of the note is different on the different instruments. The exhibit also shows people the frequency content of a sound, it is in essence a sound spectrometer. It is particularly instructive to look at the frequency content of sung vowels, this leads into a discussion of the formant frequencies in the human voice.

We'll be adding interesting info and links here. If you have a good one, we need your feedback