This image shows a typical arrangement with multiple voices loaded, perhaps in preparation for a Page R session.
Registers are logical groupings of one or more audio output channels.
The n phony indicates how many channels are dedicated to each register. Up to 8 registers can exist, as long as the total n phony does not exceed 8. The following image shows a simple Jazz rhythm section. The remaining channels are allocated to four other sounds. The default configuration allocates all eight channels to one register.