Diatonic scale

Diatonic scale (from the Greek διάτονος = by whole tones outgoing) [ διά = by, τόνος = tension, tone ] ) is a music theory term that is used to describe a respect to melody and harmony rather simple musical design, on chromaticism and enharmonic omitted. In addition, so that the tonal relationships of certain sound systems and scales are defined in more detail.

Diatonic tetrachords are Viertonfolgen consisting of two whole steps and a half step.

Diatonic scales are mostly seven- ( heptatonic ) scales that divide the Oktavraum in five full and two half steps. They differ from nichtdiatonischen conductors by the following necessary features:

  • All scale levels are derived from various stem tones, which is reflected externally in the fact that their names all start with different letters.
  • Occur no excessive or diminished intervals between adjacent stages.

(Examples: cdefgah or H -C -Dis -E - F #- G # -Ais or Des - It - Fes -Ges -As -BC )

The "traditional" diatonic scales ( major, minor, and the church modes ) also fulfill the condition that they can be composed of two diatonic tetrachords ( Adding a further Ganztonschritts ). Also, let the sounds of these scales by Quint stratification (see below) win. In an extension of this original strict definition sometimes also those scales are now referred to as diatonic, which only satisfy the condition to divide the octave into five full and two half tones. Examples are the acoustic and the altered scale. In addition, scales may be regarded as diatonic, containing less than seven tones according to current understanding, such as the anhemitonisch pentatonic conductors which divide the Otvavraum in three whole steps and two thirds.

Since the early Middle Ages diatonic scales formed the basis of Western music, first in the form of the church modes, and later as major-minor system. At the turn of the 20th century came off a part of the composer from the diatonic major-minor tonality.

Examples of diatonic and not (completely) diatonic scales

The most famous and important diatonic scales are now the major and the (natural ) minor scale: with the following distribution of whole and half steps:

In the strict sense:

  • The church modes and the cross on her back today modal scales

In a broader sense:

  • The melodic minor scale up
  • The altered scale used mainly in jazz
  • The acoustic scale
  • The anhemitonisch pentatonic ladders
  • The harmonic minor scale, because it contains an augmented second ( hiatus ).
  • The gypsy scales, because they contain excessive seconds ( hiatus ).
  • The whole-tone scale, since the last one, needed to reach the octave whole step in truth a minor third (outgoing in c notation ais - c).
  • The chromatic scale
  • The modes of limited transposition possibilities of Olivier Messiaen

Diatonic intervals

Diatonic intervals are those that are included in a ladder own diatonic scale. Specifically, these are: pure Prime, fourth, fifth and octave, small and large second, third, sixth and seventh. Although the tritone is also part diatonic conductors, but is intended as an augmented fourth, so as chromatic variant of the perfect fourth and not counted among the diatonic intervals. In contrast to chromatic (ie, excessive or decreased ) intervals diatonic intervals apply in tonal music as immediately understandable. For the distinction between diatonic and chromatic intervals, it does not matter whether the sounds involved have accidental or not. All that matters is whether the interval in question is part of a diatonic scale or not. Thus, for example, the minor third C is a diatonic interval, which, inter alia, Head intrinsically in C minor, E-flat or B- flat major occurs; at enharmonic reinterpretation of it to dis but is it a chromatic interval: the augmented second c -dis, which is not included in any diatonic scale. Accordingly, the small seconds - c of the diatonic, the excessive Prime c -cis chromatic. The small second is also called diatonic semitone, the excessive Prime chromatic semitone.

The distinction between chromatic and diatonic intervals is acoustically real only when using pure moods, in the present-day equal temperament tuning, however, the audible difference disappears. He exists then only in the score and as a mental conception that can serve for the better understanding of musical contexts.

Diatonic and chromatic semitone

Diatonic and chromatic pitches in the score

Herleitungsverfahren and History

The term diatonic is merely a demarcation to chromaticism; as the scales are constructed so that is not yet determined. These can be distanziell, harmonic or melodic derived. A more precise definition is narrower concept depends on the perspective of the respective music theorist.

One of the possible derivations based on bottom steps ( FCGDAEH ), a more common distanzielle on a sequence of whole and half steps ( whole tone whole tone whole tone whole tone - semitone - whole tone - semitone). Hermann Grabner (1886-1969) as well as the definition of Johann Georg Sulzer (1771 ) are much more detailed.

In the music of ancient Greece were as Tongeschlechter ( probably because of the exclusionary unanimity) in addition to the diatonic, the chromatic and enharmonic to the. Some of the earliest sources on the diatonic go back to Greek philosopher and mathematician. More information can be found in the descriptions of the Greek philosopher and mathematician Philolaos (Section Music Theory ), Archytas ( Music section ), Aristoxenus (Section harmonies ), Euclid (Section Music Theory ).

In late antiquity, Boethius (c. 500) describes the Pythagorean tone sequence, but still designated oktavverwandte tones with different letters. Odo of Cluny ( 878-942 ) simplified the spelling. Guido of Arezzo (c. 1025) wrote this as follows.

This is about the Pythagorean tone sequence, in which the ( Pythagorean ) whole tone, the frequency ratio of 9:8 (204 cents) and the halftone ( fourth - 2 * pyth whole tone. ), Also called limma, the frequency ratio of 256:243 ( 90 cents).

The church modes as Dorian: ahc DEFG then encompassed seven notes of the octave. Guido of Arezzo ( 1025 ) laid the basis for this by introducing staff lines and the solmization. Main article Guidonian hand.

Diatonic accordions

The term " diatonic " is often applied to accordions that reflect on train and print different tones. More precisely in this case would " wechseltönig " since the Wechseltönigkeit does not have to be diatonic.