The MIDI standard assigns note numbers to the notes of the chromatic scale, for the purpose of informing a synth what note to play in a note on message. Note numbers range from 0 to 127; note 0 is a C, note 1 a C#, note 2 a D, and so on. This is enough note numbers for ten full octaves and a partial 11th octave, which encompasses the normal range of human hearing and of all common acoustical instruments. A specific note may be given by its note number, or by a notation that uses the name of the note and an octave number. Note 60, which is usually treated as middle C, is designated C4; note 48 is C3, note 72 is C5, etc. Notice that C0 is note 12 and that note 0 is designated C-1. tNote numbers are used in the note on and note off messages, which specify the notes to be played, and in the po