Knob control over your Ensoniq ESQ. Due to ensoniq sysex characteristics knobs movements don't made realtime change in the sound until you retrigger the key on your keyboard. Also you need to configure the sysex reception in your ensoniq every time you turn your ensoniq on. There a special mode (perform mode) in the controller (you enter this mode turning the controller with all knobs at max position ) with real time control ( parameters marked with a dot in the controller ). When you are in perform mode this 3 parameters positions will not be stored if you save the patch in your ensoniq. Power supply (9v cc 500ma 2.1 pin, center positive) not included. Just plug and play. No computer required !