Triad

In music, a three-tone chord is called a triad , which in the simplest case consists of two superimposed third intervals: the pitch of the root (lower tone), third (middle tone) and fifth (upper tone). The individual tones can, however, also be octaved downwards or upwards and also occur several times. The combination Heg ¹ -h ¹ is therefore a triad, because it can be rearranged to the layering of thirds EGH.

Triads are not only important in music-making practice, but also in musical analysis, for example functional harmonics , step harmonics and cadence models . In the systematics on which the jazz chord symbols are based, each chord is built up from a major or minor triad.

Triad inversion

From left to right: basic position, first and second inversion of the major triad on c ¹

The “third-fifth shape” (third and fifth are understood here as pitches, not as intervals stacked on top of each other) is called the basic position of the chord. It can be "reversed" ( first reversal ) by octaving the bass upwards ; The second inversion is created by another upward octave of the current bass tone . The first inversion gives a sixth chord , the second inversion a fourth chord .

The inversions are only interesting for the major and minor triad, not for the excessive and diminished triad, because they do not result in any other tonal character.

species

Since a distinction is made between “major” and “minor” thirds, there are four different ways of layering two thirds on top of one another. The resulting triad types are named partly according to their tone gender , partly according to the size of their frame interval:

lower interval	upper interval	Frame interval	Triad designation	example	Example as a chord symbol (s)
major third	minor third	perfect fifth	Major triad	c – e – g	C.
minor third	major third	perfect fifth	Minor triad	c – es – g	Cm
minor third	minor third	diminished fifth	diminished triad	c – es – ges	Cm ⁻⁵ , Cm ^{♭ 5} , Cdim, C °
major third	major third	excessive fifth	excessive triad	c – e – gis	C ⁺⁵ , C aug

In addition to these four possible triads, there are also the 'Susklänge', which are mainly found in jazz and pop. Even as three-tone chords, these cannot be traced back to the layering of intervals of thirds; they lack the third degree, which is replaced by the second (Sus2) or fourth (Sus4). Such a chord thus consists of a root, a second or fourth and a fifth.

Furthermore, there are rather atypical constructs, such as the 'hard-diminished' or 'double-diminished' triad. These are seldom used and rarely mentioned in the specialist literature.

Ladder's own triads in major and minor

By layering thirds from tones of this scale (so-called scale- specific tones), triads can be formed over each tone of a scale . This is a basic idea of stage theory . In the classical theory of harmony the triads on the 1st, 4th and 5th degree of a major or minor key - referred to as the tonic , subdominant and dominant in the sense of functional theory - as the main triads.

Effect and application

A single major triad, in elementary form consisting of three tones with a vibration ratio of 4: 5: 6 in the overtone series , is often perceived as "cheerful" or "happy", while a minor triad is perceived as "sad".

The excessive triad contains more tension or a higher need for resolution due to the excessive fifth interval . It is used u. a. as a "sharpened" sound on the 5th or 1st level of a major scale .

The diminished triad also has a certain tendency to dissolve because of the diminished fifth. He is not only on the leading note in major and minor, where he strives for the tonic and therefore has a dominant function according to the function theory , but also on the second level in minor, where he does not have this tendency to dissolve and of the function theory as a representative the subdominant is described.

The inversions of major and minor triads are not perceived and interpreted as directly dissonant, but often as tense or even 'floating' compared to the basic positions. This is especially true for the sixth chord (2nd inversion). Music rarely ends on a chord that is not in its basic position. In relation to the sixth fourth chord, this comes e.g. E.g. in Stravinsky's 'Histoire du soldat' (Great Choral).

literature

Simon Sechter: The principles of musical composition . Printed and published by Breitkopf Härtel, Leipzig 1853.
Wieland Ziegenrücker: General music theory with questions and tasks for self-control. German Publishing House for Music, Leipzig 1977; Paperback edition: Wilhelm Goldmann Verlag, and Musikverlag B. Schott's Sons, Mainz 1979, ISBN 3-442-33003-3 , pp. 104–125.

Web links

Commons : Dreiklang - collection of images, videos and audio files

Wiktionary: Dreiklang - explanations of meanings, word origins, synonyms, translations

How do I create a triad (accessed October 8, 2015)

Individual evidence

↑ Mark Levine: The Jazz Piano Book . ISBN 978-3-89221-040-5 .
^ Christian Probst: SUS chords. Accessed December 6, 2018 (German).
↑ MARK NELSON: Mastering Chord Inversion for Ukulele .
↑ Everard Sigal: Composition: further triad types. Retrieved November 27, 2018 .
↑ Wieland Ziegenrücker: General music theory with questions and tasks for self-control. German Publishing House for Music, Leipzig 1977; Paperback edition: Wilhelm Goldmann Verlag, and Musikverlag B. Schott's Sons, Mainz 1979, ISBN 3-442-33003-3 , pp. 110-114.

[1] Mark Levine: The Jazz Piano Book . ISBN 978-3-89221-040-5 .

[2] Christian Probst: SUS chords. Accessed December 6, 2018 (German).

[3] MARK NELSON: Mastering Chord Inversion for Ukulele .

[4] Everard Sigal: Composition: further triad types. Retrieved November 27, 2018 .

[5] Wieland Ziegenrücker: General music theory with questions and tasks for self-control. German Publishing House for Music, Leipzig 1977; Paperback edition: Wilhelm Goldmann Verlag, and Musikverlag B. Schott's Sons, Mainz 1979, ISBN 3-442-33003-3 , pp. 110-114.