Sharp (music)

Sharp (music)
In music, sharp, (from French), or (from Greek) means, "higher in pitch". More specifically, in musical notation, sharp means "higher in pitch by one semitone (half step)". A sharp is the opposite of a flat, a lowering of pitch. The ♯ symbol itself is conjectured to be a condensed form of German ligature (for scharf) or the symbol (for "cancelled flat").
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.
Under twelve-tone equal temperament, the pitch B♯, for instance, sounds the same as, or is enharmonically equivalent to, C natural (C), and E♯ is enharmonically equivalent to F. However in other tuning systems, the enharmonic relationship is generally different from 12-EDO.
Key signature
When used as a key signature, the key is indicated by writing one or more letters to the right of the clef.
If sharps is used as a key signature, the effect continues to be applied regardless of measure and octave, unless the key changes midway or is affected by another accidental effect such as natural.
The key signature is basically applied as follows: F♯ C♯ G♯ D♯ A♯ E♯ B♯ The major scale with one sharp is G major. In all scales of the key signature for sharps, the tonic note of the major scale is a minor second above the last symbol, and the tonic note of the minor scale is a major second below the last symbol.
If there are three or more sharps, the tonic note of the minor key is the note of the third to last symbol of the key signature. For example, in the case of a minor (F♯ C♯ G♯ D♯) composed of four sharps, the third sharp from the last is C♯, which represents C♯ minor. Each new scale begins a fifth above (or a fourth below) the previous scale.
Order of sharps
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 or
Father Christmas Goes Down All Escalators Backwards or Fried Chicken Goes Down All Easy Baby.)
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.
Accidental
When used as an accidental, it is written to the left of the note head.
When used as an accidental, sharp is applied to the note following sharp within the measure. However, unlike the key signature, it does not apply to notes that have the same note name but a different octave.
However, if it is written as an accidental, all key signatures and other signs are ignored, and it is read based on the basic tone (natural tone).
To cancel the sharp used as an accidental in the same octave within the same bar, use other accidentals such as a natural (♮).
Variants
A double sharp is indicated by the symbol and raises a note by two semitones, or one whole tone. It should not be confused with a ghost note which is notated with "×".
Less often (in for instance microtonal music notation) a score indicates other types of sharps. A half sharp, or demisharp raises a note by a quarter tone = 50 cents, 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 and may be denoted .
Although very uncommon, a triple sharp can sometimes be found. It raises a note by three semitones or one whole tone and one semitone.
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).
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.
Unicode
In Unicode, assigned sharp signs are as follows:
Etc.
Historically, in order to lower a double sharp to a sharp, it would be denoted as a ♮♯ or ♯♮. In modern notation the natural sign has been often omitted. Furthermore, the same principle could be considered when canceling the symbol of a triple sharp or beyond.
Basically, up to 7 sharps can be combined in a key signature, but theoretically, 8 sharps or more can be combined, and these keys are called 'theoretical key'. In other words, double sharps can be included in the key signature.
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.
In other tuning systems except the Equal Temperaments, such enharmonic equivalences in general do not exist: In nearly every system differently notated pitches (e.g. F and G♯) are distinct.
To allow extended just intonation, composer Ben Johnston uses a sharp to indicate a note is raised 70.6 cents (ratio 25:24).
In environments where the symbol is not supported, or in text notation for specific reasons, a double sharp is sometimes written as ♯♯, ##, x or etc. Likewise, a triple sharp can also be written as ♯♯♯ or etc.
See also
Flat (music)
Electronic tuner
Notes
References
Musical notation
Pitch (music)
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