Six Sonatas for Violin and Harpsichord, BWV 1014–1019 alto solo. At first declamatory in the "forte" passages, the "piano" responses are expressive but subdued. Bach's knowledge of the expressive qualities of the violin is shown in the opening phrases, written so they can be played on the G string, the lowest string on the violin, regarded as having a "noble" tone. As explains, citing the opening of BWV 1017/3 as an example, the G string's "energy and powerful voice make it a whole instrument in itself and the lower this voice is, the more opportunity it gives to expression to attain the sublime." Around the violin melody, in
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