The augmented chords add more tension to the music and yearn for resolution. Hence they make a good replacement for the dominant chords if you want variety, a chunkier & old-time voice, and particularly if you are looking for a dreamy & mysterious sound. A 7th chord increases the tension even more before it finally resolves.
This article introduces you to the augmented 7th chords, their music theory, spelling, types, examples, dissonance, voice leading, uses, and how to play them on guitar.
Keep reading the article till the end to know all the important stuff about them!
What are Augmented seventh chords?
As you know, an augmented triad is formed by raising the 5th note of a major triad. It has two intervals of major thirds stacked over the root note with a chord formula of [1 3 #5] on a major scale. F augmented triad is made up of [F A C#] pitches.
If you add the 7th note to the augmented triads, similar to the other 7th chords, by stacking another third interval, you get the 7th augmented chords. The only difference with other 7th chords is that the third interval (between the 5th and the 7th) is a diminished third in some of these augmented 7th chords, as you will see in the later sections.
Music Theory – Augmented 7th Chord
As you know, the common types of the 7th chords are – Major 7th, Minor 7th, Dominant 7th, Half diminished 7th, and fully diminished 7th. The other types of the 7th chords are minor-major seventh chords, flat 5 seventh chords, and augmented 7th chords.
We had a brief introduction to the augmented 7th chords in our separate article on the augmented chords. An augmented chord does not occur naturally on any of the diatonic scales. We can get them from the third scale degree or the third mode of the melodic minor or harmonic minor scales.
Consider the A Harmonic minor scale with notes [A, B, C, D, E, F, G#]. The notes C, E, and G# form an augmented triad with a raised fifth note, G#. As you know, a melodic minor and a harmonic minor scale have a raised seventh, contributing to augmented harmony.
A Lydian augmented scale can be considered a major scale with the notes [1 2 3 #4 #5 6 7] and will result in augmented chords. It can also be considered the third mode of the melodic minor scale, with the raised 6th and 7th contributing to the #4 and #5 intervals.
Let us now delve deep into the main topic of the augmented 7th chords. The augmented 7ths are of two types, those formed from scale degrees 1 and 4 of a major scale by modifying a 7th Major chord and those formed by modifying the 7th dominant chords at scale degree 5.
Augmented Major 7th Chords (Maj7#5)
The Augmented Major 7th chords are also known as the Major seventh sharp 5 chords (Maj7#5). Their structure is similar to Major 7th chords, except for a raised 5th. This chord is often associated with the augmented scale (also known as the symmetrical augmented scale), which is a hexatonic scale with six notes per octave.
Definition and Examples of the Augmented Major Seventh Chord
Maj7#5 chords have four notes at the root, major 3rd, augmented 5th, and the major 7th intervals. This is equivalent to intervals of the R – M3 – M3 – m3, which can be represented by the integer notation [0, 4, 8, 11]. Note that this seventh chord has a major seventh as the highest pitch in the root position.
The chord formula for these chords is [1 3 #5 7]. It is notated as CMaj7#5 or CaugM7 or C+M7 or CMaj+7.
You can also create a Maj7#5 chord by stacking a minor 3rd interval over the augmented triad. The notes of the Maj7#5 chords with the 12 notes of Western music as their root are
CMaj7(#5) – C, E, G#, B.
DbMaj7(#5) – Db, F, A, C.
DMaj7(#5) – D, F#, A#, C#.
EbMaj7(#5) – Eb, G, B, D.
EMaj7(#5) – E, G#, B#, D#.
FMaj7(#5) – F, A, C#, E.
GbMaj7(#5) – Gb, Bb, D, F.
GMaj7(#5) – G, B, D#, F#.
AbMaj7(#5) – Ab, C, E, G.
AMaj7(#5) – A, C#, E#, G#.
BbMaj7(#5) – Bb, D, F#, A.
CbMaj7(#5) – Cb, Eb, G, Bb.
As always, the third note determines the quality of the chord. The 5th note defines the stability of the chord. Any note other than the Perfect 5th is an unstable note that may produce an unpleasing or disturbing sound. Thus raised 5th results in an unstable chord that enhances the tension.
The major 7th further enhances the Major quality of the chord but increases dissonance. This is further discussed in the dissonance section below.
Augmented Dominant 7th Chords (7#5)
The Augmented Dominant chords are also known as the augmented seventh chords, the seventh augmented fifth chords, or the seventh sharp five chords.
As is common with the dominant chords, if the word major is not mentioned specifically (like in the augmented-major 7th chords), the chord is considered the augmented dominant seventh chord. Note that while the above terms are using the words augmented seventh, they are not specifying major. Hence these are augmented dom7 chords.
Similar to the augmented major seventh chords, they derive their structure from the dominant 7th chords by raising the fifth note to #5.
Definition and Examples of the Augmented Dominant 7th Chord.
The four notes of the 7#5 chords are at the intervals of the unison, major 3rd, augmented 5th, and minor seventh from the root. This is equivalent to intervals of the R – M3 – M3 – M2, which can be represented by the integer notation [0, 4, 8, 10]. Note that this seventh chord has a minor seventh as the highest pitch in the root position.
The chord formula for these chords is [1 3 #5 b7]. It is notated as C7#5 or Caug7 or C+7.
You can also create a 7#5 chord by stacking a major 2nd interval over the augmented triad. The major 2nd interval is the same as the diminished third interval, a half step below the minor third.
The notes of the 7#5 chords with the 12 notes of Western music as their root are:
C7(#5) – C, E, G#, Bb.
Db7(#5) – Db, F, A, Cb.
D7(#5) – D, F#, A#, C.
Eb7(#5) – Eb, G, B, Db.
E7(#5) – E, G#, B#, D.
F7(#5) – F, A, C#, Eb.
Gb7(#5) – Gb, Bb, D, Fb.
G7(#5) – G, B, D#, F.
Ab7(#5) – Ab, C, E, Gb.
A7(#5) – A, C#, E#, G.
Bb7(#5) – Bb, D, F#, Ab.
B7(#5) – B, D#, G, A.
Dissonance in the Augmented 7th Chords
As stated in our separate article on “dissonance in music,” any chord is considered dissonant if any internal or outer interval is dissonant in it. The inner interval is the interval between the successive notes of the chord, and the outer intervals are the intervals between the bottom and the top notes.
All 7th chords are dissonant as the outer interval in them is a major or minor 7th.
An augmented triad is considered dissonant despite having all the consonant intervals like major 3rd and augmented 5ths. This is because diving a scale into equal parts or intervals results in imbalance and dissonance. This is exactly what happens in augmented and diminished chords with major and minor third internal intervals.
The Maj7#5 chords have the internal intervals as the major and minor 3rds, which are consonant, but it is built on an augmented triad and has a major 7th outer interval, which makes it dissonant.
The 7#5 chords have an augmented triad, a diminished 3rd, and a minor 7th, which are all dissonant.
A #5 interval is equivalent to a b13 interval and is used in the altered–extended chords.
Inversions of the Augmented 7th Chords.
The inversions of the augmented 7th chords are similar to any other 7th chords. There are three inversions denoted as 7, 6/5, 4/3, and 4/2 in the figured bass system. For example, in C major key,
The root inversion – C+M7 or I+7 has notes C, E, G#, and B.
The first inversion – C+M7/E or I+6/5 has notes E, G#, B, and C.
The second inversion – C+M7/G# or I+4/3 has notes G#, B, C, and E.
The third inversion – C+M7/B or I+4/2 has notes B, C, E, and G#.
Voice Leading & Resolution in the Augmented 7th Chords.
The augmented 7th chords resolve to a chord that is a Perfect 5th below according to the circle of fifths. Hence both III+M7 and III+7 in the harmonic minor resolve to VI or vi, which may be a major or minor chord.
Hence, G+7 and G+M7 will resolve to C. This means V+7 and V+M7 will resolve to the tonic, which can be a major or a minor chord. The raised 5th note creates a leading tone with the 3rd of the tonic note in a major mode.
Consider G+7, with the notes [G, B, D#, F]. The raised 5th note D# is a leading tone to the 3rd of the I chord [C E G]. Hence B will resolve to the C, and D# resolves to E. For any 7th chord, the 7th resolves down, so the F will also resolve to E.
You require an I chord with two 3rd notes. You may require the 5th in some cases and can omit it in others. Such an I chord is sometimes called the I3/3 chord. The diagram below shows the voice leading from the root position and the inverted V+7 chords to I3/3.
Uses of the Augmented 7th Chord
Let us now see where you can use the Augmented 7th chords in your music. Usually, it is preferred to use the 7th chords as you approach the tonic function. This is to add more tension so that the resolution is even stronger. Hence, 7th chords are more prevalent for the dominant function chords and, to some extent, for the predominant function.
This includes the V, viio, and ii chords. The use of IV7 chords is there, but less. The use of iii7, vi7, and I7 is even lesser. The same applies to the Augmented 7th chords.
Replacing the V chord
As discussed in the last section, V+7 and V+M7 resolves to the tonic chord and can be used as an altered dominant in chord progressions.
The Minor-Major Seventh Chord
You can build a minor-major 7th by adding a note a half step away from the augmented triad. Consider the C+ triad with notes [C E G#]. If you take note A, a semitone from G#, and add it as a bass to C+, you get the notes [A C E G#], which form the Minor-major 7th chord, which has an M3 interval stacked over the A minor triad.
This chord has three notes same as the C+7 chord [C E G# Bb], and one note a half step below the 7th of the C+7 chord.
Augmented 7th Chord Guitar
Maj7#5 Guitar Chord Voicings
Conclusion
Hopefully, this article on the augmented 7th chords and their use on the jazz guitar and popular music has helped you get the feel and basic understanding of the chords. Of course, You need to practice and work on your techniques to have them in your playing repertoire. Please write your comments and observations on the article in the section below.