Oud later), tuned in successive fourths. Curt Sachs said they were called (from lowest to highest pitch) "bamm", "maṭlaṭ", "maṭnā" and "zīr". "As early as the ninth century" a fifth string "ḥād" ("sharp") was sometimes added "to make the range of two octaves complete". It was highest in pitch, placed lowest in its positioning in relation to other strings. Modern tuning preserves the ancient succession of fourths, with adjunctions (lowest or highest courses) which may be tuned differently following regional or personal preferences. Sachs gives one tuning for this arrangement of five pairs of strings, d, e, a, d', g'. Historical
Violin technique other strings are not so equipped. The A string is tuned first to a reference pitch source such as a tuning fork or, in most orchestras, the oboe, typically to 440 Hz, although some orchestras tune to another standard A such as 442, or even as high as 445 or 446 Hz to produce a brighter sound. Early music groups interested in authentic performance may use a lower standard A. When playing with a fixed-pitch instrument such as a piano or accordion, the violinist must tune to accommodate that instrument. The other strings are then tuned to the A in