WTF stands for Window Transform Function, a wavetable oscillator that gives you a new and unique way to morph between waveforms.
The concept is that you have two waveforms, one in front of the other. You are then able to open a window, or gap, in the wave at the front to show a portion of the wave behind, with control over the width of the window. This let’s you create totally unique waveforms previously unobtainable, morphing between waves mid-cycle.
You can of course modulate the window width with CV, in addition you can change the front and rear waveforms with a CV.
There is also a ‘dual’ window mode so you can have two windows, as well as an ‘invert’ option for the rear waveform giving in more sonic potential. There is also a noise option for the rear waveform, the noise is also tuneable going from those nintendo-esque chip tune style noises up to white noise.