Arturia reveal KeyStep Pro at NAMM 2020 The newest, and most hotly anticipated member of the Arturia Step family is to be revealed at NAMM 2020 in Anaheim, California. The sequencer the world has been waiting for. KeyStep Pro gives keyboard players incredible sequencing and performance power in a compact, versatile controller. KeyStep Pro is a 37-key MIDI controller and multi-channel polyphonic sequencer all in one. It will allow musicians to take full control of their modular rig