The cello, or violoncello, is the second largest of the string family. It is most like the viola because they have the same set of strings: A, D, G, and C. In the orchestra, the cello normally takes the role of support and is usually the harmony as opposed to the violin's melody. It comes in four basic sizes which come in quarter increments.

The modern cello's size was standerdized in the 17oo's. The violin maker, violin family including celli, Stradivari was responsible.

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