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
String (music) invention of wound strings, such as nylon covered in wound metal, was a crucial step in string instrument technology, because a metal-wound string can produce a lower pitch than a catgut string of similar thickness. This enabled stringed instruments to be made with less thick bass strings. On string instruments that the player plucks or bows directly (e.g., double bass), this enabled instrument makers to use thinner strings for the lowest-pitched strings, which made the lower-pitch strings easier to play. On stringed instruments in which the player presses a keyboard, causing a mechanism to strike the strings, such as a