Reference : augmented sixth chords
There are at least three types of augmented sixth chords, commonly referred to as Italian, French, and German augmented sixth chords. These chords are generally used to reach the dominant when playing a cadence in major and minor keys.
The Italian Sixth
The Italian sixth chord is formed on the fourth degree. Most often it is in first inversion. Its root is raised, creating an augmented sixth interval with the bass:
Italian Sixth, A minor
Italian Sixth, A major
Note: In the case of major keys, the third of the chord must also be changed so that it has the same alterations as in the minor key. Therefore, the chord is said to be borrowed from the minor key. This also applies to the other chords of the augmented sixth and the Neapolitan sixth.
The French Sixth
The French sixth is formed on the second degree. It is a seventh chord. Most often it is in its second inversion. Its third is raised to form an augmented sixth interval with the bass:
French Sixth, A Minor
French Sixth, A major
The German Sixth
The German sixth chord is based on the fourth degree. It is a seventh chord. It is most often found in the first inversion. Its root is raised to create an augmented sixth interval with the bass:
German Sixth, A minor
To learn more about augmented sixth chords click here.
See C > Chord for related entries.
