Accidental raising the pitch of a note by one chromatic semitone (♯)
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. The ♯ symbol itself is conjectured to be a condensed form of German ligature ſch (for scharf) or the symbol ƀ (for "cancelled flat").
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 is sharp, assuming the lower one is properly pitched; regardless of proper pitch, the higher note is sharp with respect to the lower. The verb sharpen means to raise the pitch of a note by a small amount, typically less than a semitone.
Examples
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.
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]
Variants
Double sharps are indicated by the symbol
and raise a note by two semitones, or one whole tone. They should not be confused with a ghost note which is notated with "×". 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 has been often omitted.
Although very uncommon, a triple sharp (♯
) can sometimes be found. It raises a note by three semitones, or a whole tone and a semitone.[2][3][c]
Less often than double sharps (in for instance microtonal musicnotation) a score indicates other types of sharps. A half sharp, or demisharp raises a note by a quarter tone = 50 cents (Play (help·info)), and may be marked with various symbols including
. A sharp-and-a-half, three-quarter-tone sharp, or sesquisharp, raises a note by three quarter tones = 150 cents (Play (help·info)) and may be denoted
The order of sharps in key signaturenotation 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 or
Father Christmas Goes Down All Escalators Backwards.)
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♯→F
→C
, adding the double-sharped notes F
, C
, G
, D
, A
, E
, and finally B
, and similarly for the flat keys from C♭ major to C
major, but with progressively decreasing convenience and usage.
Correctly drawing and displaying 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 (depending on typeface and writing style).[citation needed]
Likewise, although the double-sharp sign
resembles a bold-face lower-case x it also needs to be presented in a way that makes the two typographically distinct.
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For the etymology of the words dièse and diesis, see Diesis.
^
The conventions of western musical notation developed when unequal meantone temperaments and well temperaments were the most widely used tunings, and equal temperament was still a theoretical proposal. For time orientation, and for example, J.S. Bach's The Well-Tempered Klavier (1722) appears to have been intended as a demonstration-piece for music writen to exploit the differences in tonality in the various well temperaments, which had been recently introduced in his time, whereas equal temperament came into common practice long after his death. Bach himself appears to have most often used something close to a 1 /6commameantone temperament; the various meantone temperaments were the prevailing systems at that time, and lingered in use for tuning pipe organs into the early 20th century. Bach's choral notation is essentially the same as in current use, and remains appropriate for all tuning systems in use during his time, and the later adopted equal temperament. The circumspect continued adherence to the same conventions Bach and his contemporaries observed for accidentals, developed prior to the near-universal use of equal temperament, ensures that music that is harmonically consonant in any one tuning system remains (very nearly) concordant any other tuning system. That is, as long as the false equivalences of invalid enharmonic substitutions – which create wolf tones – are never used (like keying F to replace an unavailable E♯, or substituting F♯ for G♭ in any unequal meantone tuning).
^
Theoretically, the same principle could be applied when canceling the symbol of a triple sharp or beyond within the same bar. However, there is no actual use case.
