A heptatonic scale is a musical scale with seven pitches per octave. Among the most famous of these are the diatonic scale, C D E F G A B C; the melodic minor scale, C D Eb F G A B C ascending, C Bb Ab G F Eb D C descending; the harmonic minor scale, C D Eb F G Ab B C; and a scale variously known as the Byzantine, Hungarian, gypsy, or Egyptian scale, C D Eb F# G Ab B C. In music, a scale is a set of musical notes that provides material for part or all of a musical work. ... In music theory, a diatonic scale (from the Greek diatonikos, to stretch out; also known as the heptatonia prima; set form 7-35) is a seven-note musical scale comprising five whole-tone and two half-tone steps, in which the half tones are maximally separated. ... A minor scale in musical theory is a diatonic scale whose third scale degree is an interval of a minor third above the tonic. ... In music, a scale is a set of musical notes in order by pitch, either ascending or descending. ...

South Indian (Carnatic music) classical theory postulates seventy-two melakarta, seven-tone scale types, whereas Hindustani classical music postulates twelve or ten (depending on the theorist) seven-tone scale types collectively called that. Carnatic music, also known as is one of the two styles of Indian classical music, the other being Hindustani music. ... Hindustani Classical Music is an Indian classical music tradition that took shape in northern India in the 13th and 14th centuries AD from existing religious, folk, and theatrical performance practices. ...

Diatonic scale

The term diatonic scale refers to a pitch collection and does not imply any particular tonal center or note of especial emphasis. It is in this respect different from the term major scale, which does imply a tonal center. In music theory, the major scale is one of the diatonic scales. ...

Melodic minor scale

In traditional classical theory the melodic minor scale has two forms, as noted above, an ascending form and a descending form. Although each of these forms of itself comprises seven pitches, together they comprise nine, which might seem to call into question the scale’s status as a heptatonic scale. In certain twentieth-century music, however, it became common systematically to use the ascending form for both ascending and descending passages. Such a use has been notably ascribed to the works of Bela Bartok and to bop and post-bop jazz practice. The traditional descending form of the melodic minor scale is equivalent to the natural minor scale in both pitch collection (which is diatonic) and tonal center.

Harmonic minor scale

The harmonic minor scale is so called because in tonal music of the “common practice period” (from approximately 1600 to approximately 1900) chords or harmonies are more commonly derived from it than from either the natural minor scale or the melodic minor scale. The augmented second between its sixth degree and its raised (“leading tone”) seventh degree, usually traditionally considered undesirable, is easily avoided by distributing these pitches among voices. In the chord progression, D F Ab, B F G, C Eb G, (ii0, V7, i in C minor) for example, the Ab in the upper voice never ascends to B, and the B in the lower voice never descends to Ab.

Melakarta

The postulated number of melakarta derives from arithmetical calculation and not from Carnatic practice, which employs far fewer scale forms. Seven-pitch melakarta are considered subsets of a twelve-pitch scale roughly analogous to the Western chromatic scale. The first and fifth melakarta tones, corresponding to the first and seventh chromatic tones, are invariable in inflection, and the fourth melakarta tone, corresponding to the fifth or sixth chromatic tone, is allowed one of two inflections only, a natural (shuddah) position and a raised (tivra) position. Thus the number of possible forms is equal to twice the square of the number of ways a two-membered subset can be extracted from a four-membered set, 2[(4!/2!2!)^2 ] = 2(6^2)=2(36)=72.

That

Hindustani heptatonic theory additionally stipulates that the second, third, sixth and seventh degrees of heptatonic scale forms (septak) are also allowed only two inflections each, in this case, one natural position, and one lowered (komal) position. Arithmetically this produces 2^5, or thirty-two, possibilities, but Hindustani theory, in contradistinction to Carnatic theory, excludes scale forms not commonly used.

See also

Diatonic and chromatic Diatonic and chromatic are important terms in Western music theory. ...