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
String instrument this method of sound production. Even though the piano strikes the strings, the use of felt hammers means that the sound that is produced can nevertheless be mellow and rounded, in contrast to the sharp attack produced when a very hard hammer strikes the strings. Violin family string instrument players are occasionally instructed to strike the string with the stick of the bow, a technique called "col legno". This yields a percussive sound along with the pitch of the note. A well-known use of "col legno" for orchestral strings is Gustav Holst's "Mars" movement from "The Planets" suite. The aeolian