A layer allows you to play two or more Parts (Patches) simultaneously (such as Piano and Strings). This is accomplished by setting two or more Parts (in a Performance) to the same MIDI channel. A split keyboard can be achieved in a similar manner by assigning multiple Parts to the same MIDI channel and then assigning different key ranges to each of the Parts. A common usage of the split keyboard is to assign a bass sound to the left side of the keyboard and a piano sound to the right.