ARCTANGENTSOFTCLIPPING

Figure 9. Clipping for various input gains � (Reiss and McPherson, 2015)

Figure 10. Effect of Gain Staging on the Magnitudes of Hard Clipping Harmonic Distortion

ARCTANGENT SOFT CLIPPING

Figure 11. Sinusoidal Input Arctangent Clipping for Various Values of �

Arctangent distortion is a form of soft clipping based on the arctangent curve.

2 � arctan(�∙�[�])

The value for � dictates the shape of the characteristic curve and the relative distortion. For this reason, the parameter � is made user controllable with a range � ∈[1,9]. The effect on a sinusoidal input and the characteristic curve for various values of � are show in (fig 11) and (fig 12).

Compared to hard clipping, arctangent clipping generates a warmer tone owing to the smoothness in the way it approaches the clipping region. The characteristic curve of arctangent clipping maintains odd symmetry for all values of � and therefore generates harmonics at odd multiples of the input frequency (fig 13).

Figure 12. Arctangent Clipping Characteristic Curves for Various Values of �

Figure 13. Odd Harmonic Distortion of Arctangent Clipping � =6