Augmented intervals and chords are difficult for beginner guitar players to incorporate into their music They may be familiar with a 7#9 chord, but not so for chords such as the augmented triad or a 7#5♭9 chord. If you understand augmented intervals, then the augmented chords, scales and modes are easy to understand and use. I cover all that and how to use the chords.
Augmented intervals, chords & scales in music
First, if you do not know all of your intervals, then you should read my Music Intervals article. Otherwise, you will not understand a lot of what I am covering. But here is a brief explanation of intervals:
Any two notes played individually or simultaneously create what is known as an interval. An interval is the distance between any two notes of the chromatic scale. The intervals can be either minor, major, diminished, augmented or perfect. We are concerned with the augmented intervals for this article.
I don’t accept goofy intervals names such as augmented 3rd or augmented prime. I understand why those interval names occur. As a matter of fact, I had to notate an interval in my Diminished Modes article as a d4 (diminished 4th).
In my opinion, there are only three augmented intervals that you will use in a chord:
Augmented 2nd: also called #9 and notated as A2, it is the 2nd note of a scale or mode that is 3 semitones above the tonic. For example, for a C chord or scale, D# is the augmented 2nd.
Augmented 4th: also called #11 and notated as A4, this is the tritone note and is 6 semitones above the tonic. For example, for a C Lydian chord or scale, F# is the augmented 4th.
Augmented 5th: also called #5 or +5 and notated as A5, it is the 5th note of a scale or mode that is 8 semitones above the tonic. For example, G# is the augmented 5th of the note C.
Enharmonic is a tern used to describe an element of music that can have two names. An example is the A# note from the chromatic scale which is an enharmonic equivalent of the note B♭. The three augmented intervals above also have enharmonic equivalents known as enharmonic intervals.
C to D# is an augmented 2nd (A2 or #9)
C to E♭ is a minor 3rd (m3 or ♭3)
D# and E♭ are enharmonic equivalents
C to F# is an augmented 4th (A4 or #11)
C to G♭ is a diminished 5th (d5 or ♭5)
F# and G♭ are enharmonic equivalents
C to G# is an augmented 5th (A5 or #5)
C to A♭ is a minor 6th (m6 or ♭13)
G# and A♭ are enharmonic equivalents
Don’t worry if that is confusing to you. I only mention it because some players may see the #9 and #11 as the ♭3 and ♭5 from the Blues scale. Let’s get into building augmented chords so you can understand the augmented intervals better.
The augmented triad and related chords
I want to focus on the augmented 5th interval, the augmented triad and the chords built off of that triad. There are 5 or 6 chords that are based on the augmented triad.
I’ll add 2 of my favorite chord voicings below each chord type. Here is an image describing all the symbols on my chord blocks:
Augmented triad: root, major 3rd, augmented 5th = 1-M3-A5 = 1-3-#5
Chord names: aug, +, #5, e.g. C-E-G# = Caug, C+ or C#5
Chord equivalent: equals an aug triad on each chord tone, Caug = Eaug = G#aug
Chord tendency: works best as a V chord, e.g. G+ > C
maj7#5: root, major 3rd, augmented 5th, major 7th = 1-M3-A5-M7 = 1-3-#5-7
Chord tendency: It sounds best to me resolving to minor triads on the P4 and M6, e.g. Fmaj7#5 > Dm (best) and B♭m
7#5: root, major 3rd, augmented 5th, minor 7th = 1-M3-A5-m7 = 1-3-#5-♭7
Chord tendency: Resolves best to its P4, but also to the m2, m3 and the minor on the M6, G7#5 > C, A♭, B♭ and Em
7#5♭9: root, major 3rd, augmented 5th, minor 7th, minor 2nd = 1-M3-A5-m7-m2 = 1-3-#5-♭7-♭9
Chord equivalent: equals a m9♭5 on the ♭7, C7#5♭9 = Bbm9♭5
Chord tendency: Resolves to the m2, P4, M6, and M7, e.g. G7#5♭9 > A♭, C, E, F#
9#5: root, major 3rd, augmented 5th, minor 7th, major 2nd = 1-M3-A5-m7-M2 = 1-3-#5-♭7-9
Chord equivalent: equals a 9♭5 on the ♭7 and a 7♭5♭13 (7#5#11) on the M3, C9#5 = Bb7♭5 = E7♭5♭13 (or E7#5#11 if you like)
Chord tendency: Resolves to major chords on the m3, P4 and m6 and minor triads on the M6 and M7, e.g. G9#5 > B♭, C, E♭, Em, and F#m.
7#5#9: root, major 3rd, augmented 5th, minor 7th, augmented 2nd = 1-M3-A5-m7-A2 = 1-3-#5-♭7-#9
Chord tendency: Resolves to practically every chromatic scale degree except the M2, A4, and P5. So for G7#5#9 the resolution or tendency to A, C# and D major are weak at best. Try every other chromatic major triad. I did not try minor triads but they probably word as well.
*7#5#11: You may occasionally see this chord name. This is a 7#5 chord with the augmented 4th added. I personally don’t use this name. I prefer the 7♭5♭13 chord name. Whichever chord name you choose, it resolves to the m2, P4, P5, and M7. So for G7#5#11 follow it with A♭, C, D or F# major.
Other chords with augmented intervals
Maj7#11: a maj7 chord with the augmented 4th interval. If you omit the perfect fifth the name is maj7♭5. You will also see maj9#11 & maj13#11
7#9: a dominant 7th chord an augmented 2nd interval added. You will also see 13#9.
7#11: a dominant 7th chord with an augmented 4th interval added. You will also see 9#11 and 13#11
Other dominant 7th chords with augmented intervals are 7♭9#11, 7#9#11 and maybe 7#9♭13. They all can act as dominant 7th chords and resolve accordingly, but due to the alterations, they have other resolutions or tendencies.
Augmented scales & modes
There are generally just two scales that are considered augmented scales. They are the whole tone scale and the augmented scale. However, there are augmented modes in both the harmonic and melodic minor scales.
Also, I’m only referencing of scales or modes that build augmented triads and augmented 7th chords. There are other scales and modes that have #11 or #9 intervals. Here are the augmented scales and modes that build the augmented chords listed above.
There are 2 different methods when it comes to the augmented scale formula. One involving augmented triads and one with alternating minor 3rds and minor 2nd intervals. I wrote an article on the C Augmented Scale chords, but here are the 6 intervals and notes:
C Augmented Scale: C-E♭-E-G-G#-B = 1-m3-M3-P5-A5-M7 = 1-♭3-3-5-#5-7
Augmented scale formula (intervals): m3-m2-m3-m2
The scale can also be looked at as 2 augmented triads separated by a half-step or semitone. In the case of C augmented that would be a C+ (C-E-G#) & a B+ (B-D#-G). Hopefully, you noticed the enharmonic equivalents in the scale. Baug has a D#, not an E♭.
Every note in the scale builds an augmented triad: C+, E+, E♭\D#+, G+, G#\A♭+, and B+.
Other than the augmented triads, the only other augmented chord that can be builts is thee maj7#5 chord on the notes C, E & G#/A♭. Here are 2 A♭maj7#5 guitar chords:
Whole tone scale
The scale formula for the whole tone scale is in the name. It is a 6-note scale where each note is separated by a whole tone. Here are the intervals and notes for the C whole tone scale:
C Whole Tone scale: 1-M2-M3-A4-A5-m7 = 1-9-3-#11-#5-♭7 = C-D-E-F#-G# and B♭.
Some websites will notate the last note as A# but I think it is better as B♭.
Every scale degree builds the same chord types. On C the possible augmented chords are C+, C7#5, C9#5 and C7#5#11 (or C7♭5♭13). Here are 2 C+ chords. The asterisk (*) on the 1st chord means it can be played at the 1st, 5th & 9th frets, and for the 2nd chord can be played at the 8th, 4th & 12th frets.
Augmented modes from the Harmonic minor scale
There is one straight-up augmented mode from the harmonic minor scale plus 2 other modes that can build augmented chords due to the #5/♭13 interval.
Here are the 3rd, 5th and 7th modes from the A harmonic minor scale:
A Harmonic minor = A-B-C-D-E-F-G#
C Ionian #5 mode = C-D-E-F-G#-A-B = 1-M2-M3-P4-A5-M6-M7 = 1-9-3-4-#5-6-7
This is technically the only augmented mode from the harmonic minor scale. You can build a C+ and a Cmaj7#5 chord.
E Phrygian Dominant = E-F-G#-A-B-C-D = 1-m2-M3-P4-P5-m6-m7 = 1-♭9-3-11-5-#5/♭13-♭7
You can choose to drop B the perfect 5th and replace it with C(B#) the augmented 5th. As a result, you can build the following augmented chords: E+, E7#5, and E7#5♭9. Any of those chords resolve nicely to A or Am.
G# Ultra Locrian = G#-A-B-C-D-E-F = 1-m2-m3-d4-d5-m6-d7 = 1-♭9-♭3-3-♭5-#5-♭♭7
The diminished 4th is actually the major 3rd and the minor 6th can double as the augmented 5th. The only augmented chord possible from this mode is the G#aug triad.
Here are 2 chord shapes for Cmaj7#5 and 2 for E7#5♭9. The 1st Cmaj7#5 chord can be played at the 1st, 5th & 9th frets.
Augmented modes from the Melodic minor scale
Similar to the harmonic minor scale, the melodic minor has one “true” augmented mode and 2 additional augmented modes. The mode built on the 4th scale degree, the Lydian Dominant, does have an augmented 4th interval, but I’ll just be covering the 3 modes that build augmented triads. I’ll use A melodic minor again as the example:
A Melodic minor = A-B-C-D-E-F#-G#
C Lydian Augmented = C-D-E-F#-G#-A-B = 1-M2-M2-A4-A5-M6-M7 = 1-9-3-#11-#5-6-7
This mode builds a C+ triad and a Cmaj7#5 chord. You also have the #11 but a Cmaj7#5#11 isn’t really a chord since it equals a G#7alt chord (see below).
E Mixolydian ♭13 = E-F#-G#-A-B-C-D = 1-M2-M3-P4-P5-m6-m7 = 1-6-3-11-5-#5/♭13-♭7
You can build E+, E7#5 and E9#5 chords from this mode.
G# Super Locrian or G Altered = G#-A-B-C-D-E-F# – 1-m2-m3-d4-d5-m6-m7 = 1-♭9-♭3-#9-3-#11/♭5-#5/♭13-♭7
This is the altered scale so you get some nice chords. You can build the following augmented chords on G#: G#+, G#7#5, G#7#5♭9, and G#7#5#9. Here are 2 G#7alt augmented chords:
When to use augmented chords
Use the chord tendencies I mentioned above. I personally never use a maj7#5 chord (I don’t like the sound of it). Jazz guys prefer that chord though as a substitute for a maj7 chord.
The maj7#11 chord is a Lydian chord and is a great chord, so use it as a IV chord or as a substitute for a maj7 on the tonic (I) chord.
As for all the dominant 7th’s with a #5, #9 or #11, they work really good as V7 chords. But when you start throwing in the ♭9, #9 and/or the #11, you can also use it as a 7alt chord or a ♭5 substitute. For example, a G7 with a #5, ♭9, #9 or #11 resolves smoothly to C (P4), F#(♭5 sub), and A♭ (7alt/leading tone).
I think I covered every augmented interval, chord, scale and mode that you will see in music unless you go to some truly exotic scales. Some of these chords are only found in jazz tunes but you should give them a try. I like all the augmented chords with maybe an exception for the maj7#5.
When it comes to playing lead over augmented chords, then there may be some scales or modes above that you can add to your toolbox. Most of these chords rarely last longer than 1 measure, so I would just use an arpeggio lick. But for you scale junkies, you can get an outside sound by choosing a mode or scale that doesn’t match the chord progression.
Check out the Augmented Music page on Wikipedia for more on augmented sounds in music.