Augmented chords are another type of chord that you can use as passing chords on the guitar, though they can also function as dominant chords. Basically, augmented chords are major chords with raised (or augmented) 5ths. They’re popular in styles of music that use dominant function and voice leading, like jazz.
An augmented triad is one of the four basic types of triads (the other three are major, minor, and diminished). An augmented triad is like a major triad with a raised 5th; it has a root, a major 3rd, and an augmented 5th: 1, 3, s5. Augmented triads don’t naturally occur in the major scale, so think of it as an altered chord — a major triad with a sharpened 5th.
Here is a comparison of four different D major chords with Daug (also written D+) chords in different positions on the neck. In each example, the 5th of D, A, is raised to form the augmented chord.
How to play augmented chord inversions
An augmented chord really just consists of a series of stacked major 3rds. For example, Caug is C, E, Gs; C to E is a major 3rd, as is E to Gs. If you add another major 3rd above Gs, you get Bs, which is the same as C.
Because of this property, to invert an augmented triad on the guitar, all you have to do is move the chord’s shape up a major 3rd two whole steps. Similarly, by moving the shape down a major 3rd on the neck, you also get an inversion of the chord.
Here are the inversions of two common augmented chord shapes on Daug. Try playing through them forward and backward to help you understand how these inversions work.
How to use augmented chords for dominant function
Having a strong sense of harmonic movement, augmented chords can produce an effect similar to dominant function with a Vaug leading to I. For instance, like V7, an augmented chord built on V has a leading tone in it that moves to the tonic pitch. The raised 5th also creates harmonic tension that resolves upward — in this case, to the 3rd of the tonic chord.
Here is an example of an augmented chord in the key of G. The Daug chord moves to the tonic chord G. The pitches in Daug are D, Fs, and As. The Fs leads to G, the root of the tonic chord. The raised 5th, As, leads to the 3rd of the G chord, the pitch B.
You hear a Daug chord and its resolution at the very beginning of Stevie Ray Vaughan’s version of “The Things That I Used to Do” (guitars tuned down one half step to Ef). The same chord an octave higher begins “School Days” by Chuck Berry, and a first inversion Gaug chord leads to C in “No One Needs to Know” by Shania Twain.
In “Crying” by Roy Orbison, you see the chord progression D-Daug-G-Gm-D-A7-D. Here, the Daug chord grows out of the D chord, functioning as a secondary dominant of G in a way that’s similar to that of a D7 chord. Orbison’s choice of chords allows for an interesting chromatic line starting on the 5th of the D chord through to the 3rd of the Gm chord: A-As-B-Bf.
Other songs that feature augmented chords include “The Warmth of the Sun” by The Beach Boys and “From Me to You” by The Beatles.