Overtones – From Wave to Source

We can hear the sound wave, but the instrument used is hidden in the dark. Is there a clear connection between the sound wave and its source, which would allow us to infer detailed characteristics of the musical instrument from the acoustic signal? We shall investigate this topic in the present station, and in the following one.

Recording the sound wave using a computer will allow us to study the time course of the amplitude in more detail. If we refine the time resolution further and further, we will see the individual fluctuations in pressure and density of the sound wave.

Compared to a sine wave with a fixed frequency, which is shown here in the form of a spinning wheel, the time course of this amplitude is much more complex. Is it possible to present this sound wave as a superposition of many different frequencies and amplitudes, that is, of many spinning wheels having matching rotation frequencies and radii?