 MIDI notes are numbered from 0 to 127 assigned to C-1 to G9.This corresponds to a range of 8.175798916 12543.85395 Hz (assuming equal temperament and 440 Hz A4) and extends beyond the 88 note piano range from A0 to C8.System Exclusive (SysEx) messages are a major reason for the flexibility and longevity of the MIDI standard.