Bowed stringed instrument popular from about 1500 to about 1750 and revived in the 20th century for early music. The viol rests vertically on the player's knees, hence its Italian name viola da gamba (leg viol).
The bow is held palm outward and is slightly convex (in contrast to the concave violin bow). Made in three principal sizes (treble, tenor, and bass), the viol has a deep body and sloped shoulders; a back that angles back sharply near the neck; a violinlike bridge; C-shaped sound holes; and tied-on gut frets that contribute to its clear, penetrating sound.
The six gut strings are tuned (in the tenor) G c f a d1 g1 (c = C below middle C; d1 = D above middle C), a tuning shared by the viol's relative, the lute. The treble tuning has the same pattern starting on d; the bass, starting on D. Less common was the double bass, tuned an octave lower; it was one ancestor of the modern double bass. In the 1500s and 1600s a consort, or ensemble, of viols was a favorite medium for chamber music by such composers as Purcell. With the rise of the orchestra in the 1700s the violin drove the treble and tenor viols from prominence. The bass viol persisted, its most famous virtuoso being the French player Marin Marais. Music for bass viol includes the Brandenburg Concerto no. 6 by J. S. Bach.
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