the collection of parallel lines and spaces on which notes are written
Mensural notation Mensural notation generally uses C and F clefs, on various lines. G-clefs, while used infrequently throughout the period, did not come into completely routine use until the later 16th century. Clefs were generally chosen to match the vocal range of a given voice, so as to avoid the need of ledger lines. Since middle C lies within that range for most voices, the C-clef is the one most frequently used. For mixed voices, a typical combination of clefs would have the bass clef (F on the fourth staff line) in the lowest voice, and tenor clef, alto clef and soprano clef (middle C on the fourth, third, and first staff line respectively) in the remaining voices. An alternative arrangement, known as chiavette, had the range of each voice shifted one third up, leading to a combination of F3, C3, C2 and G2 clefs.