“What if we had, not one Wah Wah Filter, not two, but 20?”: Implementing an M-Fold Wah-Wah Filter in Matlab

Abstract

An M-fold Wah-Wah filter can be described as an effect where multiple Wah-Wah filters are applied to a signal, each at a certain frequency range. This report describes the implementation of such a filter in Matlab. By using preexisting code on a single state-variable bandpass filter, multiple bandpass filters are implemented across a defined frequency spectrum. The filter is adjustable through a number of variables, these being: the number of bandpass filters (M), the damping factor of each filter, the spectrum for which the filters are applied, as well as the Wah Frequency, i.e. the number of cycles through each bandpass.