The cello, or violoncello, is the second-largest member of the violin family. Its range most closely matches that of the human voice, capable of reaching both deep, resonant bass notes and soaring tenor melodies. Unlike the violin or viola, the cello is played while seated, held between the knees with its weight supported by a retractable metal spike called an endpin. The endpin was only standardized in the late 19th century; before that, players held the instrument entirely with their legs. The most famous works for the instrument are J.S. Bach's 'Cello Suites,' which redefined the cello as a solo virtuoso instrument rather than just a member of the rhythm section. Its strings (C, G, D, A) are tuned exactly one octave lower than those of the viola. Because of its warm, emotive timbre, the cello is a favorite for film scores and melancholic classical compositions.