A ledger line or leger line is used in Western musical notation to notate pitches above or below the lines and spaces of the regular musical staff. A line slightly longer than the note head is drawn parallel to the staff, above or below, spaced at the same distance as the lines within the staff (see Figure 1).
Although ledger lines are found occasionally in manuscripts of plainchant and early polyphony, it was only in the early 16th century in keyboard music that their use became at all extensive (Anon. 2001). Even then printers had an aversion to ledger lines which caused difficulties in setting type, wasting space on the page and causing a messy appearance. Vocal music employed a variety of different clefs to keep the range of the part on the staff as much as possible; in keyboard notation a common way of avoiding ledger lines was the use of "open score" on four staves with different clefs (Godwin 1974, 16–17).
Notes more than three or four ledger lines above or below the staff are usually considered hard to read. When there are many notes in a passage requiring more than three ledger lines, it is often preferable to switch clef or use 8va notation. Some transposing instruments, such as the piccolo, double bass, guitar, and the tenor voice, transpose at the octave to avoid ledger lines.
Players of certain instruments prefer ledger lines to clef changes or 8va notation. Clarinetists, for example, would rather read ledger lines in the chalumeau register than read bass clef notes. Flute players would rather read ledger lines for notes in the third octave than read 8va notation because higher flute notes require different fingerings. Notation of tuba, trombone, and euphonium parts always use ledger lines below the bass staff, and never the 8va bassa notation (Read 1969, 354).
When music for bass clef instruments, such as the cello or trombone, goes several ledger lines above the bass clef, the tenor clef is used; if it were to go even higher than practical in tenor clef, the notes may be notated in treble clef, or in the case of trombone, alto clef.
- Anon. 2001. "Leger [Ledger] Line". The New Grove Dictionary of Music and Musicians, second edition, edited by Stanley Sadie and John Tyrrell. London: Macmillan Publishers.
- Godwin, Joscelyn. 1974. "Playing from Original Notation". Early Music 2, no. 1 (January): 15–19.
- Read, Gardner. 1969. Music Notation: A Manual of Modern Practice, second edition. Boston: Allyn and Bacon. Reprinted, New York: Taplinger Publishing Company, 1979.