Music/Concept/Scientific Pitch Notation
Scientific pitch notation
Overview
- Scientific pitch notation names a pitch with a letter and an octave number: C4, G1, F♯5. The letter names the note, and the number says which octave of the whole audible range it sits in.
- Middle C is C4, about 261.63 Hz. The A above it, A4, is the 440 Hz tuning note.
- It is also called American standard pitch notation (ASPN) and international pitch notation (IPN).
How the octave number counts
- The number goes up by one at each C. B3 is the note just below C4, and every note from C4 up through B4 carries the 4.
- Each octave doubles the frequency: C3 is about 130.81 Hz, C4 about 261.63 Hz, C5 about 523.25 Hz.
- An 88-key piano runs from A0 (27.5 Hz) to C8 (about 4186 Hz).
- So a "low G" can be any of several notes. G1 (49 Hz) is a deep bass note near the bottom of a bass guitar's range; G3 (196 Hz) sits just below middle C.
MIDI note numbers
- MIDI sends a note as a number from 0 to 127 and leaves naming to the software. In scientific pitch notation, note 60 is C4, note 69 is A4, note 0 is C−1 and note 127 is G9.
- Note number = 12 × (octave + 1) + semitones above C. G1 is 12 × 2 + 7 = 31, and F1 is 12 × 2 + 5 = 29.
- The frequency of note m at A440 tuning is 440 × 2^((m − 69) / 12) Hz.
- A note number carries no sharp or flat spelling. MIDI note 34 is both A♯1 and B♭1; the musical key decides which name to write.
Ableton and Arturia number octaves one lower
- Ableton/Live labels MIDI note 60 as C3, so every note name in Live's piano roll has an octave number one below scientific pitch notation.
- Arturia's MicroFreak manual counts the same way. Microfreak/UI/Front/Row/03 Bottom/01 Octave/Ref/Key Range gives the MicroFreak's keys in both namings at each octave shift.
- The bass notes that open the 05:12 chapter of GitP/A/Session/26/11/01-Sun are G1 and F1 in scientific pitch notation. Live's piano roll shows the same notes as G0 and F0.
- To compare a note name from any app or synth with one written here, find out what that app calls MIDI note 60. If it says C3, add one to its octave number.
Helmholtz notation
- Older scores and organ writing use Helmholtz notation, which marks octaves with letter case and prime marks. Middle C is c′, the C below it is c, and the C below that is C.
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