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I. Fundamentals
Seventh Chords

Core Idea

A seventh chord is a four-note chord whose notes can be arranged in thirds. A seventh chord can always be "stacked" so that its notes are either on all lines or all spaces. When a seventh chord is stacked in thirds, the lowest note is called the root, the lower middle note is called the third, the upper middle note is called the fifth, and the highest note is called the seventh, which is sometimes called the "chordal" seventh to distinguish it from the seventh scale degree.

Explanation

A seventh chord is a four-note chord whose notes can be arranged in thirds. A seventh chord can always be "stacked" so that its notes are either on all lines or all spaces.

When a seventh chord is stacked in thirds, the lowest note is called the root, the lower middle note is called the third, the upper middle note is called the fifth, and the highest note is called the seventh, which is sometimes called the "chordal" seventh to distinguish it from the seventh scale degree.

There are five common qualities of seventh chord. These qualities are the major-major seventh chord, major-minor seventh chord, minor-minor seventh chord, half-diminished seventh chord, and fully diminished seventh chord.

There is another common way of naming seventh chords: the major-major seventh chord is also often called the major seventh chord, the major-minor seventh chord is also often called the dominant seventh chord, the minor-minor seventh chord is also often called the minor seventh chord, and the fully diminished seventh chord is also often simply called the diminished seventh chord.

Within major and minor keys, seventh chords have particular qualities that correspond to scale degrees. These are the same in every major and minor key, which makes memorizing them useful.

Seventh chords are identified by their root, quality of triad and seventh, and inversion.

In this chapter, we will focus on seventh chords: four-note chords whose notes can be stacked into thirds.

Seventh Chords

Like triads, the notes of a seventh chord can always be arranged in thirds, on adjacent lines or spaces of the staff. If a triad in closed spacing looks like a snowperson, then a seventh chord in closed spacing (as in the second measure of Example 1) looks like an extra-long snowperson, with a bottom, two middles, and a head.

Example 1. A seventh chord written melodically and harmonically.

[](https://viva.pressbooks.pub/app/uploads/sites/12/2020/05/chord-members.png) Example 2. A seventh chord with the root, third, fifth, and seventh labeled. Click to enlarge.

Like in a triad, the lowest note of a seventh chord stacked in closed spacing is called the root, and the other notes are named for their generic intervals above the root, as shown in Example 2: the third, the fifth, and the seventh.

Seventh Chord Qualities and Nomenclature

Example 3 lists the five most common qualities of seventh chord: major-major, major-minor, minor-minor, half-diminished, and fully diminished. These qualities are determined by two factors:

The quality of the triad created by the root, third, and fifth (shown in the second column)

The quality of the seventh from the root to the seventh (shown in the third column)

A chord symbol for a seventh chord begins with the letter name of the triad's root followed by an indication of the quality of its triad and seventh. Examples of chord symbols for different seventh chord qualities are given in the last column of Example 3.These chord symbols reflect those used in Open Music Theory, but you may come across others in your studies. See Chord Symbols for a more thorough explanation of these variations.

Example 3. Summary of nomenclature for different qualities of seventh chord.

For the first three qualities of seventh chord, the first word describes the quality of the triad, and the second word describes the quality of the seventh:

major-major seventh chord = major triad + major seventh

major-minor seventh chord = major triad + minor seventh

minor-minor seventh chord = minor triad + minor seventh

The other two qualities are both built on diminished triads but differ in the quality of the seventh:

half-diminished seventh chord (diminished triad, minor seventh)

fully diminished seventh chord (diminished triad, diminished seventh)

Music theorists often use the names described above, but there is also another common way of naming these chords, given in parentheses in the first column of Example 3:

The major-major seventh chord is also often called the major seventh chord.

The major-minor seventh chord is also often called the dominant seventh chord.

The minor-minor seventh chord is also often called the minor seventh chord.

The fully diminished seventh chord is also often simply called the diminished seventh chord.

The half-diminished seventh chord does not typically have an alternate name.

Your instructor may have you label these chords using one set of terminology or the other, or a mix of both.

Example 4 summarizes all this information in music notation.

Example 4. The qualities of sevenths and triads in various seventh chord types.

Don't forget that when the root of a seventh chord has an accidental, you add that accidental into its name. For example, B♭mi7 is the chord symbol for a seventh chord with a B♭ minor triad and a minor seventh. Likewise, a G♯ma7 is the chord symbol for a seventh chord with a G♯ major triad and a major seventh.

In chord-symbol notation, if a pitch class other than the chord's root is the lowest note in a seventh chord, then a slash is added, followed by a capital letter denoting the pitch class in the bass (lowest) voice. Example 5 shows a G half-diminished seventh chord (G∅7). In the first measure, the chord appears in first position; in the second measure, the chord's seventh (F) is in the bass voice, so the chord symbol is written as G∅7/F. This topic will be explored more in the chapter Inversion and Figured Bass.

Example 5. Two seventh chords.

Listening to Seventh Chords

Listen carefully to the different qualities of seventh chord in Example 4. It is common to pair expressive qualities with seventh chords when learning what they sound like. You might think of major-major seventh chords as sounding "happy and jazzy," major-minor seventh chords as sounding "unresolved" (like they strongly need to move to another chord), minor-minor seventh

Key Quote

A seventh chord is a four-note chord whose notes can be arranged in thirds.

Application Scenarios

Like triads, the notes of a seventh chord can always be arranged in thirds, on adjacent lines or spaces of the staff. If a triad in closed spacing looks like a snowperson, then a seventh chord in closed spacing (as in the second measure of Example 1) looks like an extra-long snowperson, with a bottom, two middles, and a head.

Example 1. A seventh chord written melodically and harmonically.

[](https://viva.pressbooks.pub/app/uploads/sites/12/2020/05/chord-members.png) Example 2. A seventh chord with the root, third, fifth, and seventh labeled. Click to enlarge.

Like in a triad, the lowest note of a seventh chord stacked in closed spacing is called the root, and the other notes are named for their generic intervals above the root, as shown in Example 2: the third, the fifth, and the seventh.

Key Terminology

fully diminished seventh chordhalf-diminished seventh chordmajor-minor seventh chordminor-minor seventh chordmajor-major seventh chorddiminished seventh chorddominant seventh chordmajor seventh chordminor seventh chordclosed spacingchord symbolsseventh chord
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Related Links

Source: https://viva.pressbooks.pub/openmusictheory/chapter/seventh-chords/
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