Cubic Soft Clipper

In §9.1.6, we used the cubic soft-clipper to simulate amplifier distortion:

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

This function is diagrammed in Fig.6.22. It is non-invertible when driven into ``hard clipping''.

Figure 6.22: Cubic nonlinearity.