Who says chords just Sheryl

The structure of chords

Jürg Hochweber

A chord is the harmony of three or more tones, which usually have a certain structure (namely layering of thirds). Sometimes two notes count as a chord. So what a chord is is not sharply defined.
The basis for building chords is the major scale, which is assumed to be known here. We want to focus here mainly on the key C major limit, but of course everything should be mastered in all keys.

In this text, individual tones are designated with lower case letters (c, d, e ...), chords in the common symbol script in upper case letters (C, G, Am, D7 ...).
Chords are typically used to accompany a melody sung or played. The following are possible:
Piano, guitar, accordion, harp but also a group of wind instruments etc.

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1. Intervals (= distances)

A third is always the distance from one note to the second next in the scale. For example, c - e is a major third because it comprises two whole steps. On the other hand, e - g is a minor third because it only comprises a half and a full step.
Similarly, c - a is a major sixth, but e - c is a minor sixth.c - h is a major seventh, d - c is a minor seventh.

2. Triads

The simplest and by far the most common chords are the triads. A C major triad consists of the tones:
c - e - g.

So we go from the root c to the second next in the scale, e, then on to the second next, g.
A C major triad consists of two thirds layered on top of each other, first a major, then a minor. It is simply referred to as C.

If, in the same way, we stack up the next but one note f from tone d, and then again the next but one a, we get that D minor triad (Dm):

.

Here we have a minor third first, followed by a major third.

A major triad basically consists of a major and a minor third.
A minor triad basically consists of a minor third and a major third.

We still speak of a triad if, for example, a high c is added to the C major triad c –e - g. Any number of octave doublings of the chord tones can even be added, the chord is still called a triad (if the third is the leading tone, however, it is usually not doubled).

The keynote does not always have to be at the bottom. The tones can be rearranged, one then speaks of Reversals. So you are allowed to use the terms Keynote (which gives the chord the name) and Bass tone Do not confuse (lowest chord note). A C major triad can e.g. E.g. be built like this:
e - g - c - g.
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In a triad c - e - g, we call c the root note, e 'the third', and g 'the fifth' for the sake of simplicity. (Correctly, one should actually say for 'the third': the tone that is a third above the fundamental).
The C chord is also called the 1st degree (from C major) or the tonic (from C major).

Here are some forms of the C major triad. They are all labeled with C. In addition, there are some forms of the D minor triad, consisting of the tones d - f - a, denoted by Dm: play

The symbol font C Am G etc. allows a lot of freedom. Depending on the context, instrument, style and knowledge, one takes one form or the other.
In the same way, triads are formed from the other notes of the C major scale. We then get the following chords:
 C.DmEmF.GAt theHm-
stepI.IIIII;IVV.VIVII
Soundsc e gd f ae g hf a cg h da c eh d f

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if we form a triad starting from b, we get the sound b - d - f, which consists of two minor thirds. We call this a diminished triad Hm- or Hm5- or Hdim (diminished, diminué), since the interval h - f is a diminished fifth. Since it is mostly perceived as the upper part of the G7 chord, it has little independence. (It should be remembered that in English an H is referred to as a B, a German B is a Bb in English)

These would be the head own Triads of C major. They are the only triads that do not contain accidental notes. Simple songs or pieces in C major are limited to these chords, or even manage with just two or three (C, G, F).

See also: C major and its relatives

In terms of structure, we only have the types:

- Major triad
- minor triad
- diminished triad.

In addition, there is the excessive triad c - e - g sharp, which consists of two major thirds.

It is referred to as C + or C5 +. Since the G sharp appears in it, it does not belong to the ladder's own chords of C major (e.g. it belongs to harmonic A minor).

3. Four notes

If we add another third to a triad G, we get a four-note chord, a so-called seventh chord g - b - d - f, which is referred to as G7. It is very common in C major. The tone f is then simply called 'the Sept' designated.

Seventh chord it is called because the new note f is the seventh note of the root note g (in C major scale). In G7, g - f forms a minor seventh. If we form a seventh chord c –e - g - b from c, then we have a four-note chord with a major seventh c - b.

This sound is rarer and is called differently, Cj7, Cmaj7, C7 # or C7 +. The 'maj' or 'j' comes from major, which means greater (or major).

Note that the chord C7, i.e. with a minor seventh, does not belong directly to the key of C major, since the tone b occurs. (It belongs to F major or D minor)

Seventh chords can also be formed from the other ladder-specific triads by adding another third:

Hm7 / 5- h d f a 7th stage
On the 7tha c e g 6 stage
G7g h d f 5th stage
Fig. 7f a c e4th stage
Em7e g h d3rd stage
Dm7 d f a c 2nd stage
Cj7c e g h 1st stage
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With the sound Hm7 / 5- that means 5- that the fifth h - f is diminished. Likewise, a + would mean an increase.

These are all four notes of C major that have no accidentals.

So we have the following types in terms of structure:

- G7 (major third, minor third, minor third)
- Cj7, Fj7 (major third, minor third, major third)
- Dm7, Em7, Am7 (minor third, major third, minor third)
- Hm7 / 5- (minor third, minor third, major third)

Also with the four chords (seventh chords) any octave doubling of the chord tones can occur. Any tone can also be used as the lowest tone (bass tone), but in practice not all are used equally and certain rules should be observed when connecting chords. In the seventh chord, the fifth (i.e. the third chord note) can often be left out without losing the character of the sound. The G7 often only consists of the tones g - h - f (or forms like g - g - f - h).

Here are some seventh chords: (Again, I limit myself to the key of C major)

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5. General principle

What I have said so far can be generalized: most chords are obtained by stacking thirds. A G7 / 9 can be made from the G7 by simply adding the a to the notes g h d f, i.e. the note after the next, that is, we add another third.
so we get e.g. the following five notes (seventh non chords or simply ninth chords):

As can be seen in the example, the ninth can also be altered (changed). On the A7 / 9- the ninth is lowered, on the E7 / 9 + it is raised. So there are so many options.

Now, however, in a piece that contains seventh-non-chords, there will hardly only be chords from the root key, but chords from other keys. Or the chords are altered (changed). Altered chords can of course also occur with three or four notes.

Examples:

Altered triads:
C + consisting of
c - e - g sharp. It's called excessive triad. Here the fifth was increased by g zugis.

Altered four notes:
G7 / 5 + consisting of
g h dis f. Here the fifth d has been increased to dis.
Note that there is no normal third-octave structure here, since the last interval dis - f actually sounds like a second. However, since the f is regarded as the next but one note of D, one speaks of a (diminished) third.

G7 / 5- The fifth is lowered to des. Here, too, there is no real structure of a third.

Altered five notes:
G7 / 9- consisting of g h d f as. The ninth a was lowered to as. As with the four notes, the fifth and sometimes the third can be left out of the five notes.

Minor chords can also be extended with the ninth:
Am7 / 9 consists of a c e g h. The possibilities of alteration are limited, however. So a raised ninth (dis) would simply result in a minor third (es). And a raised fifth in the triad would result in the sound a - c - eis = a - c - f, which is nothing more than an F major triad!
In the ninth chords, inversions are less common. So z. E.g. the ninth rarely appears in the bass. How all these sounds are then skillfully combined with one another is an art in itself and cannot be dealt with here.

Now the basic principle of the structure of chords has become clear. Put simply, the only difference between the chords is the way in which major and minor thirds are layered on top of one another (and possibly reversed and doubled). But a chord like G7 can have completely different functions in different contexts, see G7 resolutions.
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I would now like to systematically show all combinations of three and four notes with a table. I always start with chords with the smallest possible intervals (minor third, minor third, minor third) and end with major intervals (major third, major third, major third).
In the case of the five notes, I unsystematically selected some of the common ones. All chords are built up from the root c (but do not necessarily belong directly to the key of C major).

6. More chords

Theoretically, countless six and seven notes could be formed by adding further thirds, but these are seldom complete and cannot be dealt with systematically.

Is meant with z. E.g. with G7 / 9/11 a chord where another third is stacked:

g - h - d - f - a - c

Unfortunately, the chord symbols are used quite inconsistently and imprecisely here. Sometimes the symbol G11 is simply used, and it is left open whether the 7 and 9 are automatically included. Incidentally, this already applies to the symbol G9, which may or may not contain the 7.
You have to know that the chord symbol writing was not invented by scholars, but arose from practice in different places, and is not standardized.

A 13 means that another third is added, the 13th note counting from the root note.

Examples:
G7 / 13 or G7 / 6 usually only with the tones g f h e.
G7 / 11 + with the tones g h f a c sharp.

That would also have to be mentioned Lead chords:
In a sequence like G7 - C, the f from G7 can still overlap a little into the chord, so that the sound C4 emerges, which is made up of the notes
c f g exists.
Or in other words: in the C chord, the third e is replaced by the fourth f. Since C4 usually follows C, such a sound has little independence and is more of a melodic element.
The f in C4 becomes Fourth lead called, English suspended fourth, hence sometimes the name Csus4.

Csus9 is formed similarly: c e g d. (here comes the dadditionally, not in place of c)

7th fourth chords

Instead of the third structure, chords with a fourth structure are also formed. Pure or excessive fourths can be used. However, they have not grown historically and can hardly be incorporated into a theoretical structure, but they have a special charm. Some quart sounds:

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It is also possible to build a fifth instead of a fourth, but the sounds of fifths are much less common.

8. Power chords

In pop music, the symbols C5, G5 etc. often appear, which are somewhat illogically called power chords. It is nothing more than chords without the third.


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So C5 only contains the notes c and g, possibly with octave doubles. It is therefore an open question whether they are perceived as major or minor chords.

Chord progressions like:
A5 G5 C5 A5 D5 C5 G5 E5 A5 G5 C5 A5 F5 G5 A5
are heard more as an amplified bass melody:
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9. Clusters

Clusters are tonal chords that contain notes that are very close together. When a sound counts as a cluster is of course a matter of judgment. They are very easy to play on the piano; only a few clusters are possible on the guitar.


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10. Symmetries in some chords

Let us consider the excessive triad C + with the notes c - e - g sharp, consisting of two major thirds! If we go a major third from G sharp, we get back to the keynote c. Since we do not differentiate between the inversions in the chord names, this means that every tone is equivalent, it could also be E or G sharp root.

So C + E + and G # + are the same. The excessive triad is a symmetrical chord. (Of course, the designation C + suggests that there should be a c in the bass, but this does not have to be the case).

The situation is similar with the diminished seventh chord Cdim7 with the notes c es ges a. It consists of lots of minor thirds. From the last note to the root note there is again a minor third. He is also referred to as a co. So you can also say here:

Cdim7 = Ebdim7 = Gbdim7 = Adim7

Finally, we also find a symmetry in the chord C7 / 5- with the notes c e ges b. It consists of a major third, a minor third (corresponds to one second) and a major third. If we do the same structure from ges, we get with;

ges b c e the same chord again.
So you can equate C7 / 5- with Gb7 / 5- again.

This shows all symmetries. There are theoretically some very unusual chords with symmetries like the chord:

c - e - g sharp - b - d - f sharp, which consists of all whole steps or a chord:

des - f - a - c - e - gis, which consists of two nested augmented triads (Db + and C +).

It is a good practice to investigate that there are in fact no other symmetries and that the root of the remaining chords is clearly determined. For example, if we take the G7 chord and try to use the note d as the root note, we can reinterpret as much as we want, we cannot build a third.

This is also the reason why chord names like C6 are superfluous.
C6 means a C major chord with an added sixth: c - e - g - a.
If we change this sound, we simply get the Am7 chord with a - c - e - g.
C6 is not to be confused with the figured bass number of the Baroque, where a C sixth chord only means an inversion to e - g - c.

It takes a lot of practice to be able to quickly identify the underlying structure of a third from a group of a few notes, especially since for practical reasons a G is often written where a F sharp should logically be.

11. 'Chords in Chords'

I already mentioned that the diminished triad
Hdim with the notes h - d - f
is contained in the chord G7 = g - b - d - f.
It is similar in other cases, and it is useful to remember some of them. Examples:

As you can see in the table, the chord Cj7 / 9 contains both an Em and a G.

In the last example in the table you can see how the diminished 7th chord is part of the G7 / 9-. You could also say that every diminished 7th chord is a 7/9 without a root. Incidentally, this approach also explains the different resolutions of the diminished 7 chords. look here.

A chord c - e - (g) - b - d flat - f sharp could theoretically be numbered with Cj7 / 9 + / 11 +.But it is probably more appropriate to speak of bitonality here: a B major chord lies above a C major chord.

So much for the chord structures. A treatise on chord connections and voice leading in different styles would now be much more comprehensive. For a scientific presentation, I recommend the well-known work 'Harmonielehre' by Arnold Schönberg.
see also: chord progressions

Please send comments to [email protected]
© 2001 by Jürg Hochweber
rev. 2004, 2017, 2010

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