it is used to vary sounds by utilizing dedicated effects that can be controlled by expression pedal. but the effects are limited and permanently assigned- glide, tempo, etc. it is really not versatile or customizable like a midi foot controller is. behringer makes a small unit that can be set to control specific actions via midi as well as the fcb1010 foot controller. both are better suited for keyboards. look st the bcr series desktop midi controllers on behringer website.