Chapter 4
Accidentals & Enharmonics
by Will Nelson
The pitch names we’ve discussed so far (A, B, C, D, E, F, and G) only account for seven of the twelve pitches within an octave. To name each of the twelve pitches, we modify the seven “natural” pitches with accidentals. The two most common accidentals are the flat (♭), which lowers a pitch by a half step, and the sharp (♯), which raises a pitch by a half step. The pitch B♭, for example, is one half step lower than the pitch B. Conversely, the pitch F♯ is one half step higher than F.
Another common accidental is the natural (♮). The natural undoes a previous accidental. For example, a B♮ following a B♭ cancels the flat and raises the pitch back up a half step.
Two other accidentals alter a natural pitch by a whole step. The double flat (♭) lowers a natural pitch a whole step (or a flat pitch by a half step) and the double sharp () raises a natural pitch by a whole step (or a sharp pitch by a half step).
Accidentals make it possible for one pitch to have multiple names or “spellings.” For instance, F♯ (one half step above F) sounds the same as G♭ (one half step below G) because they share the same key on the piano. Pitches like F♯ and G♭ are enharmonically equivalent, meaning they sound the same even though they have different names.
A composer’s choice of one enharmonic pitch over another generally relates to that pitch’s function within the music. For instance, a composer might use a D♯ when a melody ascends to E or an E♭ when a melody descends to D.
unit 1a · Foundations of Tonal Music: Pitch