Sharp (music)

From Wikipedia, the free encyclopedia
For the use of the sharp sign in mathematics, see Musical isomorphism. For the use of the sharp sign in computational complexity theory, see ♯P.
"♯" redirects here. It is not to be confused with Number sign or well-field system.

In music, sharp, dièse (from French), or diesis (from Greek)[a] means, "higher in pitch". More specifically, in musical notation, sharp means "higher in pitch by one semitone (half step)". Sharp is the opposite of flat, which is a lowering of pitch.

A sharp symbol, ♯, is used in key signatures or as an accidental. For instance, the music below has a key signature with three sharps (indicating either A major or F♯ minor, the relative minor) and the note, A♯, has a sharp accidental.

{ \override Score.TimeSignature #'stencil = ##f \relative c'' { \clef treble \key a \major \time 4/4 \hide Staff.TimeSignature ais1 } }

Under twelve-tone equal temperament, B♯, for instance, sounds the same as, or is enharmonically equivalent to, C natural (C♮), and E♯ is enharmonically equivalent to F♮. In other tuning systems, such enharmonic equivalences in general do not exist. To allow extended just intonation, composer Ben Johnston uses a sharp to indicate a note is raised 70.6 cents (ratio 25:24), or a flat to indicate a note is lowered 70.6 cents.[1]

In intonation, sharp can also mean "slightly higher in pitch" (by some unspecified amount). If two simultaneous notes are slightly out-of-tune, the higher-pitched one (assuming the lower one is properly pitched) is "sharp" with respect to the other. Furthermore, the verb sharpen means to raise the pitch of a note, typically by a small musical interval.

Variants[]

Double sharps are indicated by the symbol double sharp and raise a note by two semitones, or one whole tone. They should not be confused with a ghost note which is notated with "X". Historically, in order to lower a double sharp by one semitone to a sharp, it would be denoted as a ♮♯. In modern notation the natural sign is often omitted.

{ \override Score.TimeSignature #'stencil = ##f \relative c'' { \clef treble \key c \major \time 4/4 \hide Staff.TimeSignature bisis2 bis2 } }

Less often (in for instance microtonal music notation) a score indicates other types of sharps. A half sharp raises a note by a quarter tone = 50 cents (About this soundPlay (help·info)), and may be marked with various symbols including half sharp. A sharp-and-a-half (or three-quarter-tone sharp) raises a note by three quarter tones = 150 cents (About this soundPlay (help·info)) and may be denoted three quarter sharp.

{ \override Score.TimeSignature #'stencil = ##f \relative c'' { \clef treble \key c \major \time 4/4 \hide Staff.TimeSignature dih1 eisih } }

Although very uncommon, a triple sharp (♯triple sharp) can sometimes be found. It raises a note by three semitones.[2][3]

Correctly drawing and printing the sharp sign[]

The sharp symbol (♯) resembles the number (hash) sign (#). Both signs have two sets of parallel double-lines. However, a correctly drawn sharp sign has two slanted parallel lines that rise from left to right, to avoid obscuring the staff lines. The number sign, in contrast, has two completely horizontal strokes in this place. In addition, while the sharp also always has two perfectly vertical lines, the number sign (#) may or may not contain perfectly vertical lines (according to typeface and writing style).[citation needed]

Order of sharps[]

Main article: Circle of fifths

The order of sharps in key signature notation is F♯, C♯, G♯, D♯, A♯, E♯, B♯, each extra sharp being added successively in the following sequence of major keys: C→G→D→A→E→B→F♯→C♯. (These are sometimes learned using an acrostic phrase as a mnemonic, for example:   Father Can Grab Dogs At Evenings Best   or   Father Charles Goes Down And Ends Battle   or   Father Christmas Gave Dad An Electric Blanket   or   Fat Cows Go Down And Eat Buttercups.)

Similarly the order of flats is based on the same natural notes in reverse order: B♭, E♭, A♭, D♭, G♭, C♭, F♭ Battle Ends And Down Goes Charles's Father or Blanket Exploded And Dad Got Cold Feet, encountered in the following series of major keys: C→F→B♭→E♭→A♭→D♭→G♭→C♭.

In the above progression, the key of C♯ major (with seven sharps) may be more conveniently written as the harmonically equivalent key D♭ major (with five flats), and likewise C♭ major (with seven flats) may be more conveniently written as B major (with five sharps). Nonetheless, it is possible to extend the order of sharp keys yet further, through C♯→G♯→D♯→A♯→E♯→B♯→Fdouble sharp→Cdouble sharp, adding the double-sharped notes Fdouble sharp, Cdouble sharp, Gdouble sharp, Ddouble sharp, Adouble sharp, Edouble sharp and finally Bdouble sharp, and similarly for the flat keys from C♭ major to Cdouble flat major, but with progressively decreasing convenience and usage.

Unicode[]

In Unicode, assigned sharp signs are as follows:

  • U+266F ♯ MUSIC SHARP SIGN (HTML ♯ · ♯)
  • U+1D12A