Clef
A clef (from French: clef 'key') is a musical symbol used to indicate which notes are represented by the lines and spaces on a musical staff. Placing a clef on a staff assigns a particular pitch to one of the five lines or four spaces, which defines the pitches on the remaining lines and spaces.
For other uses, see Clef (disambiguation).
The three clef symbols used in modern music notation are the G-clef, F-clef, and C-clef. Placing these clefs on a line fixes a reference note to that line—an F-clef fixes the F below middle C, a C-clef fixes middle C, and a G-clef fixes the G above middle C. In modern music notation, the G-clef is most frequently seen as treble clef (placing G4 on the second line of the staff), and the F-clef as bass clef (placing F3 on the fourth line). The C-clef is mostly encountered as alto clef (placing middle C on the third line) or tenor clef (middle C on the fourth line). A clef may be placed on a space instead of a line, but this is rare.
The use of different clefs makes it possible to write music for all instruments and voices, regardless of differences in range. Using different clefs for different instruments and voices allows each part to be written comfortably on a staff with a minimum of ledger lines. To this end, the G-clef is used for high parts, the C-clef for middle parts, and the F-clef for low parts. Transposing instruments can be an exception to this—the same clef is generally used for all instruments in a family, regardless of their sounding pitch. For example, even the low saxophones read in treble clef.
A symmetry exists surrounding middle C regarding the F-, C- and G-clefs. C-clef defines middle C whereas G-clef and F-clef define the note at the interval of a fifth above middle C and below middle C, respectively.
Two common mnemonics for learning the clef lines are:
Before the advent of clefs, the reference line of a staff was simply labeled with the name of the note it was intended to bear: F, C, or sometimes G. These were the most common 'clefs', or litterae clavis (key-letters), in Gregorian chant notation. Over time the shapes of these letters became stylised, leading to their current versions.
Many other clefs were used, particularly in the early period of chant notation, keyed to many different notes, from the low Γ (gamma, the G on the bottom line of the bass clef) to the G above middle C (written with a small letter g). These included two different lowercase b symbols for the note just below middle C: round for Bâ™, and square for Bâ™®. In order of frequency of use, these clefs were: F, c, f, C, D, a, g, e, Γ, B, and the round and square b.[12] In later medieval music, the round b was often written in addition to another clef letter to indicate that Bâ™ rather than Bâ™® was to be used throughout a piece; this is the origin of the key signature.
In the polyphonic period up to 1600, unusual clefs were occasionally used for parts with extremely high or low tessituras. For very low bass parts, the Γ clef is found on the middle, fourth, or fifth lines of the staff (e.g., in Pierre de La Rue’s Requiem and in a mid-16th-century dance book published by the Hessen brothers); for very high parts, the high-D clef (d), and the even higher ff clef (e.g., in the Mulliner Book) were used to represent the notes written on the fourth and top lines of the treble clef, respectively.[13]
The practice of using different shapes for the same clef persisted until very recent times. The F-clef was, until as late as the 1980s in some cases (such as hymnals), or in British and French publications, written like this:
In printed music from the 16th and 17th centuries, the C clef often assumed a ladder-like form, in which the two horizontal rungs surround the staff line indicated as C: ; this form survived in some printed editions (see this example, written in four-part men's harmony and positioned to make it equivalent to an octave G clef) into the 20th century.
The C-clef was formerly written in a more angular way, sometimes still used, or, more often, as a simplified K-shape when writing the clef by hand:
In modern Gregorian chant notation the C clef is written (on a four-line staff) in the form and the F clef as
The flourish at the top of the G-clef probably derives from a cursive S for "sol", the name for "G" in solfege.[14]
C clefs (along with G, F, Γ, D, and A clefs) were formerly used to notate vocal music. Nominally, the soprano voice parts were written in first- or second-line C clef (soprano clef or mezzo-soprano clef) or second-line G clef (treble clef), the alto or tenor voices in third-line C clef (alto clef), the tenor voice in fourth-line C clef (tenor clef) and the bass voice in third-, fourth- or fifth-line F clef (baritone, bass, or sub-bass clef).
Until the 19th century, the most common arrangement for vocal music used the following clefs:
In more modern publications, four-part music on parallel staffs is usually written more simply as:
This may be reduced to two staffs, the soprano and alto sharing a staff with a treble clef, and the tenor and bass sharing a staff marked with the bass clef.
For use with computer systems, the Unicode Consortium has created code points for twelve different clef symbols as part of a repertoire called the "Musical Symbols" block. Although much of the list was established by 1999, general provision of these symbols in common computer fonts remains rather limited.[b] The clef symbols provided are these: