Augmented Triads

An augmented triad is a 3-note chord built by stacking two major 3rds. The term “augmented” comes into play because the interval from the root of the chord to the 5th is an augmented 5th. Another helpful approach for constructing an augmented triad is to begin with a major triad and then raise the 5th by a ½ step. (Think: Root, 3rd, ?5).

Major 7(#5) Chords

Major 7(?5) Chords combine an augmented triad with a major 7th (Think: Root, 3rd, ?5, ?7). Building this chord on the note C, we get C–E–G?–B. Common chord symbols for this chord include C?(?5), C?+ and Cmaj7(?5). You may even see this chord written as a slash chord, E/C.

Dominant 7(#5) Chords

Dominant 7(?5) Chords combine an augmented triad with a minor 7th. (Think: Root, 3rd, ?5, ?7). Building this chord on the note C, we get C–E–G?–B?. Common chord symbols for this chord are C7+ and C7(?5). This chord is often associated with the Whole Tone Scale, particularly when the ?9 is included, as in C9(?5). However, C7(?5) is also found in the Altered Scale, where it can be voiced with either the ?9 or ?9.

Where do augmented chords come from?

Augmented chords can sometimes be confusing for music students. Certainly, one contributing factor is that out of the four types of triads (major, minor, diminished and augmented), the augmented triad is the only one that does not occur naturally within the major scale. Rather, the augment triad is a diatonic chord that occurs in both the Harmonic Minor Scale and the Melodic Minor Scale (ascending only). In both scales, the augmented triad occurs as the 3-chord (?+) as a result of the raised 7th scale degree.

The following examples notate and demonstrate the A Harmonic Minor Scale with its corresponding diatonic triads and 7th chords on piano. Notice that it is the 3-chord that produces the augmented chords (C+ and C?+).

Augmented Triads and Harmonic Function

Even though the augmented triad occurs in both the Harmonic Minor and Melodic Minor scales as a ?+ chord, it rarely functions this way. In other words, most augment triads you’ll encounter won’t make sense as a 3-chord of a minor key. More often, augmented triads will appear to be a ?+, ?+ or ?+ in a major key. However, as we’ll see later in this lesson, the augmented 5th interval usually results from chromatic voice leading over a major triad (?, ? or ?). In such cases, the presence of the augmented 5th interval is best understood as a passing tone.¹

In addition to the Harmonic Minor Scale and the Melodic Minor Scale, there is an additional scale that is also closely associated with augmented chords. The Whole Tone Scale produces augmented triads and dominant 7(?5) chords on each scale degree. For a deep dive on the Whole Tone Scale, check out our Quick Tip on Whole Tone Scale—The Complete Piano Guide (Int).
How many augmented triads are there?

Unlike most other chords which have 12 unique transpositions, there are only 4 unique augmented triads. This is because most other chords are asymmetrical (with the exception of fully-diminished 7th chords). However, the symmetrical structure of augmented chords means that all its chord tones are equidistant. In fact, the interval from the 5th of the chord up to the root is also a major 3rd. Therefore, an augmented triad divides the octave into 3 equal parts. Each part is comprised of 4 half-steps (or a major 3rd). Let’s take a closer look by constructing augmented triads on the roots C, D?, D and E?.

Symmetrical Structure = Limited Transpositions

Suppose we were to build an E Augmented triad. This chord is spelled E–G?–B?. However, these are the exact same notes as C Augmented (C–E–G?). In fact, C Augmented in first inversion (C+/E) is identical to E Augmented in root position. As a result, augmented triads don’t have an identifiable root, as far as the ear is concerned. How can this be? Well, it’s similar to the fact that a chromatic scale doesn’t produce or imply any identifiable tonic note.

How to Spell Augmented Triads

Perhaps you’re wondering why some of these augmented triads are spelled as such? One might protest, “Is it really necessary to spell B Augmented as B–D#–F??? (Note, the ?? symbol represents “double-sharp”). Why not spell it B–D#–G?” The answer has to do with what we mean when we use the words “triad” and “root.” Remember, triad does not mean a chord with 3 notes—that’s a frequent misconception. For example, a sus chord like Gsus4 (G–C–D) is not a triad, even though it contains 3 notes. Instead, the term triad means a 3-note chord that can be arranged as a stack of 3rds (Think: Root–3rd–5th). Since Gsus4 cannot be arranged as a stack of 3rds, it is not a triad. However, it still has a root…the note G. The root is the fundamental note upon which a chord structure is built. Sus4 chords use the structure 1–4–5.

So why can’t B Augmented be spelled B–D#–G? Actually, in one sense it can, and in another it cannot. The notes B–D#–G are still a triad because they can be stacked in 3rds. For example, if you rearrange the notes in the order G–B–D#, then you have a stack of 3rds with a clear root-position triadic shape. However, B is no longer the root! The root of G–B–D# is the note G, and that chord is named G Augmented.

So, is there a difference between G Augmented and B Augmented? The sound is identical when they are arranged with the same note on bottom. However, they come from different Harmonic Minor Scales. For example, G Augmented is the ?+ chord of E minor, whereas B Augmented is the ?+ chord of G? minor. In modern practice, most arrangers opt to spell augmented chords in a manner that is easiest to read.

Triad Pairs (Intermediate)

Professional jazz musicians frequently improvise by drawing on a melodic device known as triad pairs. To improvise with triad pairs, jazz pianists select two complimentary triads from a common scale and then create melodies that alternated back and forth between these triadic shapes.

Generally speaking, pianists prefer to pair adjacent triads from their source scale. This way, the triad pair will not have any common tones. In other words, one triad pair typically contains 6 unique notes. If you were to choose non-adjacent triads from the source scale, the resulting common tone(s) will reduce your total number of notes.

Let’s consider an example of triad pairs to bring this concept into sharp focus. For this illustration, we’ll create a triad pair with two augmented chords: C Augmented (C–E–G?) and D Augmented (D–F?–A?). These two triads are adjacent chords drawn from the C Whole Tone Scale (C–D–E–F?–G?–A?).

The first step to improvise with triad pairs is to practice “blocking” the selected pair through each inversion. This familiarizes your hand with the shapes that you’ll be alternating between when improvising with the selected triad pair. Therefore, we’ll start by playing C+ and D+ in root position. Then, we’ll continue to ascend through each inversion. Afterward, it’s a good idea to practice playing the triad pair in descending blocks too.

Source Scale for the Dominant 7(?13) Sound

You may be wondering where this voicing comes from? Notice that when we resolve A?7(?13) to D?6/9, our melodic line includes the ?9 and the ?9. In this case, the source scale for A?7(?13) is the A? Altered Scale, which is technically spelled as A?–B??–C?–D??–E??–F?–G?–A?. However, that is a nightmare to try to read! Therefore, it’s much more helpful to think of the parent scale enharmonically as the G? Altered Scale, which is G?–A–B–C–D–E–F?. Do you see the C Augmented triad (C–E–G?) contained within the scale? Since this specific example is uses the Altered Scale, the chord symbol A?7alt is also appropriate here. If you are not yet familiar with the Altered Scale, be sure to check out our Quick Tip on The Altered Scale—The Complete Guide.

In other cases, a Dominant 7(?13) chord symbol does not necessarily imply a fully altered sound. In fact, since this particular voicing only contains 4 notes (A?–C–E?–G?), it’s impossible to pin down a specific source scale or parent scale without a musical context. For example, all of the following scales produce the Dominant 7(?13) sound.

    Mixolydian?13 Scale: 1–2–3–4–5–?6–?7
    Phrygian Dominant Scale: 1–?2–3–4–5–?6–?7
    Altered Scale: 1–?2–?3–?4–?5–?6–?7
    Whole Tone Scale: 1–2–3–?4–?5–?6


et’s find our C Augmented upper structure triad in each scale built on the root of A?. The notes of C+ are underlined for you.

    A? Mixolydian?13 Scale: A?–B?–C–D?–E?–F?–G?
    A? Phrygian Dominant Scale: A?–B??–C–D?–E?–F?–G?
    G? Altered Scale: G?–A–B–C–D–E–F?
    A? Whole Tone Scale: A?–B?–C–D–E–F?

Why is this important? There are two reasons. First, you want to be sure to associate the UST ?+ voicing with each potential chord symbol, which includes V7(?13), V7(?5) and V7alt. Secondly, when you are improvising, if you see a V7(?13) chord symbol, just know that it doesn’t always represent the same scale, so a little detective work is in order. You could choose any of the scales shown above. However, a good rule of thumb is to look to the melody to supply the harmonic context, as we did in the example above.

C Augmented UST Over Other V7(?13) Chords

Earlier, we discussed the symmetrical structure of augmented triads and examined how each augmented triad shape has three unique spellings. Since C Augmented has two other spellings, it should come as no surprise then that it can serve as a UST for two additional V7(?13) chords. If fact, the roots of the three V7(?13) chords that share C+ as an UST outline an augmented triad themselves. In other words, C+ works as a UST for C7(?13), E7(?13) and A?7(?13). Moreover, it’s not even necessary to change the spelling of the UST.

C Augmented UST Over Other V7(?13) Chords

Earlier, we discussed the symmetrical structure of augmented triads and examined how each augmented triad shape has three unique spellings. Since C Augmented has two other spellings, it should come as no surprise then that it can serve as a UST for two additional V7(?13) chords. If fact, the roots of the three V7(?13) chords that share C+ as an UST outline an augmented triad themselves. In other words, C+ works as a UST for C7(?13), E7(?13) and A?7(?13). Moreover, it’s not even necessary to change the spelling of the UST.

Augmented USTs for Lydian Dominants

We can also use Augmented USTs to voice the Lydian Dominant sound. We get these brilliant and uplifting dominant chords from the Lydian Dominant Scale. This scale uses the scale degrees 1–2–3–?4–5–6–?7.

Let’s begin by considering the D Lydian Dominant Scale. This scale is  D–E–F?–G?–A–B–C?–D. Do you see the C Augmented triad (C–E–G?) contained in this scale? Since C+ naturally occurs in this scale, we can use it as an upper structure triad to voice the Lydian Dominant sound, just like we did for the Dominant 7(?13) sound. We simply need to add a D7 chord shell in the left hand.

You might ask, “But wait, won’t this sound the same as the Dominant 7(?13) voicing?” No, because the relationship of the augmented triad to the root of the dominant 7th chord is different, as we’ll soon see.

C Augmented UST Over Other Dominant 9(?11) Chords

Of course, there are two other Lydian Dominant chords that share C Augmented as and upper structure. They are G?9(?11) and B?9(?11). Notice that the roots of these related Lydian Dominants outline an augmented triad: G?–B?–D.

Let’s play an example using G?9(?11), shown below. Notice, for this chord, the C Augmented upper structure is not spelled quite correctly, enharmonically speaking. Technically, the 7th of G?7 is the note F?, not E?. However, it is much easier to read this voicing by spelling the right hand as a C+ upper structure and the left hand as a Root+3rd chord shell.

Since the C Augmented triad is built on the #4 of G?7, we can call this a UST #?+. However, what key has G?7 as a 5-chord? How about C? major—yuck! Therefore, we’ll spell this Lydian Dominant enharmonically as F?9(?11) and we’ll resolve it to B major. However, our UST is not #?+ anymore. It is now a UST ??+. This is a minor detail, but one worth noting.

We have one more Lydian Dominant chord that can use C Augmented as and upper structure. Let’s play our augmented UST for B?9(?11).

Augmented USTs for Minor-Major 7th Chords

We can also the augmented triad as a UST for Minor-Major 7th Chords. Jazz pianists frequently substitute minor-major 7th chords in place of regular minor 7th chords, especially in contexts in which the minor chord is not a 2-chord. For example, pianists sometimes play a I–? as the final chord of a minor 2-5-1 progression. In addition, jazz pianists frequently use inner voice movement to create voice leading from  R??7??7??6. This melodic gesture passes through a minor triad, a minor-major 7th chord, a minor 7th chord and a minor 6th chord, all with the same root (see example below).

Let’s play Am(maj7) using a C Augmented UST. Our right hand will play C–E–G? while our left hand plays an open 5th with the notes A and E. Since our right is playing the ?7 (the note G?), we must be sure to not play the ?7 in our left hand (the note G?). However, you can play the ?6 in the left hand if you want.

