Some Patches contain a Filter section for a different approach to sculpting the sound. The Filter is a key component of audio production and is designed to remove (filter out) frequencies from a sound.
In the Patch, “Toy Piano – Classic Shiny,” the Lo Cut knob controls the cutoff frequency of a high-pass filter, where frequencies below the cutoff are removed. When the knob is fully-clockwise, most of the bass response has been filtered out.
Hi Cut attenuates everything above a preset cutoff frequency. Turning the knob all the way to the left yields a darker sound.