Distortion

Distortion (or nonlinear distortion) is any efffect that changes the shape of a sine wave to something else. Distortion effects are used in electric guitar sounds and in simulating acoustic musical instruments. For example ,we use a nonlinear effect in the flute example to model how the air in a flute interacts with the incoming breath pressure. You can read about other kinds of commonly used distortion here.

In this example, we distort a sine wave with quadratic and cubic terms.

What happens if instead of a single sine wave, we apply a nonlinear distortion to the sum of two sine waves? Notice how quadratic and cubic distortion have different effects on the sound spectrum.

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