Cubic Soft Clipper

In §4.13, we used the cubic soft-clipper to simulate amplifier distortion:

$$f(x) = \left\{\begin{array}{ll} -\frac{2}{3}, & x\leq -1 \\ [5pt]... ...{3}, & -1 \leq x \leq 1 \\ [5pt] \frac{2}{3}, & x\geq 1 \\ \end{array}\right.$$

This function is diagrammed in Fig.S.2. It is non-invertible when driven into ``hard clipping''.

Figure S.2: Cubic nonlinearity.