The RSP-550 features MIDI compatibility which significantly increases its versatility. Using the MIDI IN jack, it is possible to call up any of the 199 patches from a MIDI foot pedal (such as the BOSS FC-50) or a MIDI sequencer.
The RSP-550 also responds to up to four individual realtime MIDI controller messages which allow you to alter specific parameters in real time using an expression pedal. These messages include aftertouch, velocity, pitch bend, modulation, and note number. Using the MIDI OUT jack, it is possible to save
all of your custom programs via system exclusive bulk dumps to a BOSS BL-1 Bulk Librarian or MIDI sequencer.