In Part 1 we explained how the tones of most real instruments can be reduced to patterns of harmonics, which can be generated using sine, saw, square or pulse waveforms. This month, we consider the sonic raw materials needed to imitate unpitched percussion.
The theremin is one of the oldest electric instruments around, and its distinctive sound is instantly recognisable. However, real ones are hard to find, and even harder to play. Sam Inglis tries to work out a way of cheating.