chord

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In music, a chord is the simultaneous sounding of different tones that can be interpreted harmonically .

Origin of the word

The term chord is derived from the French accord (both first 'agreement', 'accord of feelings', then also '[musical] harmony'), which in turn comes from the vulgar Latin accordare 'to bring into agreement' , 'adapt', 'harmonize' '(from Latin cor ' heart ' ). In addition, the Greek χορδή chordḗ , German string ”, had an effect on the word , probably since late Latin, and perhaps strengthened its application to the musical field. Originally the term stood for “consonance”, ie for the production of the same tone on different strings. It was used by Michael Praetorius as early as 1619 . It was not until 1732 that the term appeared in the sense of "harmony of different tones", which can also be related to the sounding of the overtone series of a single tone.

Explanation

In real music, chords are formed from the harmony of many voices that have different functions: melody, bass, accompaniment or filler voices. The treatment of the chords in individual voices becomes clearest in the four-part movement . However, tones can also be heard in a single voice that are experienced by the listener as common components of a harmonic structure. This means that chord breaks ( arpeggios ) and the slow build-up of sounds (e.g. Rachmaninoff , Melodie Op. 3 No. 3, penultimate measure) are chords in the sense described. How chords are actually used in music depends on the genre . Polyphony (horizontal structure, several independent voices, for example in a fugue ) and homophony (vertical-chordal structure, for example in a song with guitar accompaniment) can be seen as opposing poles .

Types and structure of chords

Usually at least three different notes are called a chord. However, there are also combinations of only two tones (two-note chords) that still fulfill chordal functions. The fifth to the full triad is then often missing . But since the fifth is already present in the natural overtone spectrum, such a two-tone can fully represent a triad. Often two chords ( English dyad ) are used in rock music in the form of a power chord , i.e. only the root and fifth without the third . There is also the fourth harmonic with structures in which a pure fourth is clearly preferred. The relatively young fourth harmonic can be seen as a deliberate contrast to the traditional third harmonic.

Layering of thirds

From triad is when the three sounding pitches itself - possibly after octave transpositions - the third interval above the root note of the chord "layers" can, for example, CEG .

The following applies to chords of the third harmonic :

  • two superimposed different thirds (first major, then minor or vice versa) result in a major or minor chord;
  • two equal thirds (major and major or minor and minor) result in an augmented or diminished chord;
  • three superimposed thirds result in a seventh chord ;
  • four superimposed thirds result in a non chord ;
  • five superimposed thirds result in an undecimal chord ;
  • six superimposed thirds result in a tredezima chord .

Chords that are not layered in thirds or that are layered in such a way, the root note of which does not sound at all, can be mentally supplemented with third-layered chords in accordance with the respective musical context, or they can be explained in some other way (e.g. by leads). For example, the triad egb can function as a dominant seventh chord cegb in a corresponding context . Something like this should be checked in the context of the piece, as there are often several possible interpretations.

Analysis of chords

When counting the different notes in a chord, only different note names are taken into account regardless of their pitch. After this transformation, the tones of the chord contained are named as intervals to the lowest tone of the chord, in the example mentioned as third and fifth to the lowest tone, although they actually existed as fifths and decimals. The specific name of the chord depends on the naming system.

Chord location

The term "position" has two meanings in connection with chords:

C major triad in different positions (the black note heads indicate “gaps”):
a: octave position / wide, b: third position / narrow,
c: fifth position / mixed, d: border position
  • the treble position indicates which tone appears in the soprano (treble). Depending on whether, in a triad of the highest-sounding tone root, third or fifth, is called octave -, third - or fifth position , with more sounds and of sixth - Sept - Non - Undezim - and Tredezimlage . The octave range was also called the “basis” in the past .
  • the spacing characterizes the distance between the three upper parts. A distinction is made between: wide location , narrow location , mixed location and, as a special case, the border location .
    • Wide range : the distance between the three upper voices is so great that a chordal tone could be inserted between soprano and alto, as well as between alto and tenor. The wide range is particularly popular in the four-part choral setting.
    • Close position : the three upper parts are so close that no chordal note fits in between. The distance between soprano and tenor is then less than an octave, so that the three upper parts can be easily grasped with the right hand when composing the piano. The narrow position is preferred especially when playing figured bass.
    • Mixed range : between soprano and alto there is a narrow range, between alto and tenor wide range or vice versa. A special case of the mixed register is the borderline position , in which the distance between soprano and tenor is exactly one octave.

Chord inversions

To determine the inversion of a chord, the lowest note (the bass note) is decisive, regardless of whether the chord sounds in a narrow or wide register.

The inversions are named after characteristic intervals measured from the lowest note. The individual names (see below) come from the figured bass technique.

Triads

Triad inversions

Triads can occur in their basic position and in two inversions:

  • Basic position , e.g. B. in C major: c '- e' - g ' ; the basic position can be recognized by the layering in thirds;
  • 1st inversion , in this example e '- g' - c '' , called a sixth chord , since it is nothing special that there is a third below, but that from the lowest to the highest note it is a sixth instead of a fifth;
  • 2. Inversion, in this example g '- c' '- e' ' , called sixth fourth chord , since both fourths instead of thirds in the lower part of the chord and sixths instead of fifths are to be noted as the frame interval.

Four notes

Inversions of 7th chords

Seventh chords can appear in their basic position and in three inversions:

  • Basic position, e.g. B. G 7 : g - h - d '- f' , again recognizable by the layering of thirds, called a seventh chord , because the additional seventh distinguishes it from a triad;
  • 1st inversion, in this example b - d '- f' - g ' , called the fifth sixth chord , since the fifth and sixth occur simultaneously above the lowest note;
  • 2. Inversion, in this example d '- f' - g '- h' , called the third fourth chord , since the third and fourth occur simultaneously above the lowest note;
  • 3. Inversion, in this example f '- g' - h '- d' ' , called the second chord , since the second above the lowest note is the characteristic of it.

Other four chords that are not seventh chords can of course also be reversed, but the above designations for the individual inversions do not apply to them. An example of this is the triad with added sixth ( sixte ajoutée ), which in its basic position is basically a fifth sixth chord, but has a completely different function than the identically structured 1st inversion of a seventh chord, so that one should avoid this confusion of terms.

Five and multiple sounds

A four-part chord to which one (five-tone) or more tones in the interval of thirds (ninth, undezime, tredezime) has been added to the scale is called a five-tone and multi-tone chord. These sounds are usually very colorful due to secondary rubbing and are used in the composition for special moods. Sometimes in classical music (here most commonly as the dominant seventh note chord), but far more often in jazz, as the tones added to the three and four notes (also known as "tension notes") form the basis for the tension-laden jazz harmonic.

Chord naming systems

Several independent systems are used for naming chords, which are briefly outlined below:

  • The bass note of the chord and the intervals above it ( figured bass )
  • The degree of the chord in terms of the degree theory
  • The function of the chord in terms of function theory
  • The key of the chord and the lowest tonally relevant tone as well as additions, see chord symbol

The naming systems are listed in the order in which they historically came about. Each new system has taken over a large part of the achievements of the old systems (especially with regard to the syntax of the modifications compared to the basic triad) and developed them further. The basic structures of chords are therefore mentioned in the oldest description system, the basso continuo, no longer in the subsequent ones, although they are also used there.

Bass tone and intervals

This type of description is mainly used in figured bass . The chord is named after the intervals that the tones it contains occupy the lowest note.

Basic triad
The intervals of thirds and fifths are normal and are therefore not mentioned. The chord marked by the lack of further information is therefore (e.g. in the basic key of C major ) a basic triad above the note c.
Sixth chord
The fifth can be replaced by the sixth to create a sixth chord ( c - e - a ). Like the basic triad, the sixth chord is considered a regular sound.
Quart lead
In the chord, the fourth can replace the third ( c - f - g ). In traditional classical music it is felt as if the fourth had displaced the third from its place. Therefore, this sound has to be resolved by the voice performing the fourth bringing the third as the next tone [ceg].
Fourth text lead
The combination of fourth and sixth in a chord ( c - f - a ) is understood as an extension of the previous case. Both tones must be resolved: c - e - g . These variants only became common after the baroque period. Nonetheless, the term “Quartsextvorhalt” has been retained, which plays an important role especially for cadenzas in concerts of the Viennese classical music.
reduced
The semitone steps in the basic scale result in diminished chords for certain basic tones , i.e. basic triads from two minor thirds on top of each other, c - es - gb or b - d - f . This leads to a diminished fifth, which gave the sound its name. The name is also used when the diminished fifth is notated as an augmented fourth: c - es - f sharp .
Sixth fifth chord
The fifth is named because it sounds in addition to the sixth that normally replaces it. Sixth fifth chords are described as subdominant or dominant in function theory. The subdominant variant (also sixte ajoutée ) adds the sixth to a basic triad ( f - a - cf - a - c - d ), while the dominant variant is based on a diminished triad ( h - d - gh - d - f - g ). The conceptual distinction comes from the functional-theoretical analysis, and thus from the historically earlier appearance of the sixte ajoutée chord in a subdominant function in contrast to the dominant seventh chord.
excessive sixth fifth chord
It sounds like the dominant seventh chord and enables modulation into other keys or has a spatial effect. The augmented fifth chord is e.g. B. (f - a - c - dis) with the excessive sixth f-dis. It sounds like the F major seventh chord and can e.g. B. to E major / minor, C major / minor, A major / minor, with the excessive sixth tending towards the octave ee.
Seventh chord
The ladder's own seventh is added to the basic triad , which depending on the position can be large ( c - e - gc - e - g - h ) or small ( dominant seventh chord ) ( g - h - dg - h - d - f ) .

step

The naming of the steps is a further development of the naming via the base note, which, in contrast to this, describes the tonal classification of the chord in the harmonic context.

All of the above-mentioned chord types can be identified in a corresponding manner, whereby the reference note is not a specific base note, but instead the number of this base note in the scale of the base key.

Examples in C major:

  • the sound c - e - g is a basic triad above the first level;
  • the sound g - h - d - f is called the seventh chord above the fifth degree.

This system of sound description is used in level theory .

Sound supply

Chords consist of the set of notes made available by the respective musical context. In the case of traditional Western music, these are the twelve notes of the chromatic scale and their repetitions in different registers.

Since traditional western music is based for the most part on a basic key, there is a core tone reserve from the 7 so-called ladder-specific tones.

  • In the case of C major these are: c, d, e, f, g, a, h.

In order to temporarily change to other keys in the musical sequence, this tone supply can be expanded to include tones that differ from the basic key in the other keys. In fact, the modulation (the change) occurs through the introduction of tones that are not related to the conductor. The most typical extensions that lead to alterations from the ladder's own tones to tones outside the ladder are the minor seventh and the excessive fourth.

  • In the case of C major these are: b instead of b and f sharp instead of f.

The alteration from B to B is perceived as a harmonic swing in the direction of the next key in the circle of fifths, which counts this tone to its own ladder.

  • In the case of C major, this is F major.

This panning is also felt if no sound is formed on the basis of F major, but only a seventh chord over c ( c - e - g - b ), for example . Modulations to keys that are further away expand the tone stock from which chords can be formed.

key

While the figured bass and the theory of degrees make the note stock of the basic key the starting point for their naming, the chords can also be understood directly as representatives of a key . For this, the tones contained are evaluated.

Examples:

Within a piece is in C major

  • the sound f - a - c is an F major triad,
  • the sound c - e - a is an A minor triad in the 1st inversion
  • and the sound d - f - g - h a G major seventh chord in the 2nd inversion.

This designation is clearer than “IV. Level "or" I. Level sixth chord ”, but refrains from integrating the named sound into the harmonic context of the piece.

function

The function theory describes chords on the basis of kinship relationships that result from the circle of fifths arise. Here, too, the chord types described above can be used and expanded with further four-, five- and multi-notes.

The basis of the sound is the key, which is named due to its functional relationship to the basic key. Since this does not describe the keynote of the chord, an indication is also given of the inversion or the interval that the keynote has in relation to the root of the function described.

The above examples lead to the following designations:

Chord symbol

Jazz notes are commonly distributed as lead sheets with singing voice and chord symbols .

The jazz chord symbol as a notation corresponds in the broadest sense to a figured bass notation in which the root note is explicitly specified as a note name in letter form. A bass note that deviates from the root note is also determined, separated by a slash (see: Slash chord ). Chord modifications are indicated by information on the gender of the sound, digits and other abbreviations.

Comparison of naming systems

The respective naming systems reflect the understanding of harmony of the time in which they were created. While the figured bass notation is a pragmatic abbreviation in the typeface, the step theory builds up a first harmonic connection that is extremely extended by the function theory. The jazz notation adopts the syntax that has arisen up to then, but completely abandons the functional context that is not always necessary in jazz.

The example of the diminished seventh chord over c sharp ( c sharp - e - g - b ) in a C major context shows how these differences are expressed:

  • Figured bass : bass tone acis, indication 7 ♭
  • Level theory : ♯I 7 ♭
  • Functional theory : DDD 7 9 ♭ , if the chord resolves to the double dominant D major, or ( D 7 9 ♭ ) Sp, if it resolves to the subdominant parallel D minor. (Strikethrough marks the missing chord root, brackets an intermediate dominant.)
  • Jazz : C♯ ° 7

The diminished seventh chord is outside the usual cadence , but is not unusual for Bach either. One can see that the thoroughbass, by dispensing with any explanation, notices the sound, which is unusual for it, without any problems, while the step theory has to modify its basic construct (the step) and the functional theory needs further information for the correct designation. The notation habits in jazz are pragmatically similar to the figured bass.

In return, functional theory can realize its advantages when it comes to describing sounds that were unthinkable in the time of the figured bass or the theory of stages. This is the case, for example, with sounds in which the third occurs simultaneously as a major and a minor third, which would functionally be notated as a third and an excessive second / ninth , or with sounds that can no longer be clearly related to a keynote like the " Mystic chord " layered from fourths by Alexander Scriabin (c-fis-b-e'-a'-d ") as well as the " Tristan chord "by Richard Wagner , with which the opera " Tristan und Isolde "begins.

Chord accompaniment in the song

In songs , chords are usually used as instrumental accompaniment . They give the melody a harmonic reference in sections. The chord accompaniment is mostly played with a polyphonic keyboard or string instrument (e.g. piano or guitar ).

The sequence of chords is called a progression . If the chord progression repeats itself cyclically (e.g. |: G, Em, C, D7: |) it is called a harmonic ostinato .

Motivation from the overtones

The tones of a major chord are distinguished from other tones in that they represent the first integer subdivisions of the vibration of the fundamental.
Halving the wavelength results in the first octave, in thirds the second fifth and fifth the third major third of the fundamental. The next higher or lower octave of these tones results from doubling or halving the frequency.

These overtones , which also occur naturally with the fundamental tone in practically all sound production, are perceived as being in harmony with the fundamental tone. The real overtones also depend on the instrument producing the sound and are only given here as an example.

Since these ratios cannot be precisely tuned for all basic tones in the pure tuning of a keyboard instrument, the same tempered tuning has mostly been used since the 19th century , which only ensures an exact frequency relationship for the octaves.
The twelve intermediate tones of an octave are chosen so that the frequency ratio to the next semitone is always identical.
This results in slight deviations in the frequency ratio to thirds and fifths of a few cents , but every note can be used as the root of a chord.

See also

literature

  • 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. 104–135 ( From the chords and the harmonic relationships ).

Web links

Wiktionary: chord  - explanations of meanings, word origins, synonyms, translations
Commons : Chords  - collection of images, videos and audio files

Individual evidence

  1. ^ Entry “accord” , in: Le Trésor de la Langue Française informatisé .
  2. Article “ 2 Akkord”, in: Etymological Dictionary of German . Developed at the Central Institute for Linguistics, Berlin, under the direction of Wolfgang Pfeifer. Deutscher Taschenbuchverlag, Munich 1995, p. 21.