(Redirected from Arabian tone system)The modern 'Arab tone system', or system of
musical tuning, is based upon the theoretical division of the
octave into twenty-four equal divisions or 24-tone
equal temperament (24-TET), the distance between each successive
note being a
quarter tone (50
cents). Each
tone has its own name not repeated in different octaves, unlike systems featuring
octave equivalency. The lowest tone is named ''yakah'' and is determined by the lowest
pitch in the
range of the singer. The next higher octave is ''nawa'' and the second ''tuti''. (Touma 1996, p.17-18) However, from these twenty-four tones seven are selected to produce a
scale and thus the interval of a quarter tone is never used and the three-quarter tone or
neutral second should be considered the characteristic interval. (ibid, p.23)
By contrast, in the European
equally tempered scale the octave is divided into twelve equal divisions, or exactly half as many as the Arab system. Thus the system is written in European
musical notation using a slashed flat for
quarter flat, a flat for half-tone
flat, a slashed flat and a flat for
three-quarter tone flat, sharp with one vertical line for
quarter sharp, sharp (♯) for half-step
sharp, and a half sharp and a sharp for
three-quarter sharp. A two octave range starting with ''yakah'' arbitrarily on the G below middle C is used. (ibid, p.24)
In practice far fewer than twenty-four tones are used in a single performance. All twenty-four tones are individual pitches differentiated into a
hierarchy of important pitches, "pillars", which occur more frequently in the
tone rows of traditional music and most often begin tone rows, and scattered less important or seldom occurring pitches (see
tonality). (ibid, p.24-25).
The specific notes used in a piece will be part of one of more than seventy
modes or
maqam rows named after characteristic tones which are rarely the first tone (unlike in European-influenced music theory where the
tonic is listed first). The rows are
heptatonic and constructed from
augmented,
major,
neutral, and
minor seconds. Many different but similar ratios are proposed for the frequency ratios of the tones of each row and performance practice, as of 1996, has not been investigated using electronic measurements. (ibid, p.18) Actual practice is estimated to vary within a quarter tone from notation.
The current tone system is derived from the work of
al-Farabi (d. 950 CE) (heptatonic scales constructed from seconds) who used a 25 (unequal) tone scale (see
tetrachord), with
Mikha'il Mishaqah (1800-1889) first presenting the 24 tone equal tempered division. (ibid, p.19)
Source
★ Habib Hassan Touma (1996). ''The Music of the Arabs'', trans. Laurie Schwartz. Portland, Oregon: Amadeus Press. ISBN 0-931340-88-8.