Violin typically are lower in pitch than the G-string; these strings are usually tuned to C, F, and B. If the instrument's playing length, or string length from nut to bridge, is equal to that of an ordinary full-scale violin; i.e., a bit less than , then it may be properly termed a violin. Some such instruments are somewhat longer and should be regarded as violas. Violins with five strings or more are typically used in jazz or folk music. Some custom-made instruments have extra strings which are not bowed, but which sound sympathetically, due to the vibrations of the bowed
Basic physics of the violin pitch, which may be described in terms of frequency. The playing tension of a violin string ranges from about to . The length of the string also influences its pitch, and is the basis for how a violin is played. Violinists "stop" a string with a left-hand fingertip, shortening its playing length. Most often the string is stopped against the violin's fingerboard, but in some cases fingertip contact alone is enough to stop the string at the desired sounding length. Stopping the string at a shorter length has the effect of raising its pitch. String material affects the quality of