Stringed instrument, the tenor member of the violin family. In appearance it is almost identical to the violin but slightly larger; its strings are tuned a fifth lower. It is a member of many chamber music ensembles, and the modern orchestra uses 6 to 10 violas. Its tone is darker, warmer, and less powerful than the violin's, and it is rarely employed as a solo instrument. The viola d'amore is an 18th-century instrument with six or seven melody strings, under which are strung several sympathetic strings that resonate in concord with the sounded pitches.