Exploring Augmented Sixth Chords: A Musician's Guide to Enigmatic Harmonies

Are you ready to unlock the enigmatic world of augmented sixth chords? These unique chords often appear in classical music, jazz, and even contemporary genres, bringing a rich, complex harmonic texture that adds a touch of unpredictability. Understanding them can be a game-changer, helping to elevate your music to new levels of sophistication. This guide dives deep into the realm of augmented sixth chords, providing step-by-step guidance, real-world examples, and actionable tips to help you master these fascinating harmonic elements.

Understanding Augmented Sixth Chords

Augmented sixth chords are intriguing chords that produce an unexpected tension, creating an almost “unfinished” quality in music. These chords often appear in transitional sections, bridges, and modulators. Their mysterious allure comes from their dissonant nature, which can be resolved in various ways, depending on the context. The most common types of augmented sixth chords are the Neapolitan augmented sixth, the French augmented sixth, the Italian augmented sixth, and the German augmented sixth.

Quick Reference

The Neapolitan Augmented Sixth

The Neapolitan augmented sixth (often abbreviated as N6) is a major chord built on the lowered second scale degree of the relative minor. In C major, this would be an F# chord. This chord typically functions as a pivot chord, leading into the dominant or subdominant. Here’s a detailed look into how you can use the Neapolitan augmented sixth in your music:

Building the Chord

To build a Neapolitan augmented sixth chord, start with the relative minor scale. For example, in C major, the relative minor is A minor. From the A minor scale, construct a major triad using the lowered second degree (F#):

The Neapolitan augmented sixth chord in A minor would be F# major with an added sixth (E):

F# major with the added sixth (E) gives us the notes: F#, G#, A, B, C#, E.

Harmonic Function

The N6 chord serves several key functions:

• Leading to the dominant or subdominant.
• Adding tension that resolves naturally to the dominant chord.
• Piquing the listener’s curiosity due to its unexpected dissonance.

For instance, in C major, you might have the sequence G major (dominant), F# major augmented sixth (N6), and then to Em (vi) and C major (I).

Practical Application

Let’s look at a practical example in a simple C major chord progression:

In this sequence, the F# major chord with the sixth (E) adds an intriguing layer of complexity before resolving to D minor and eventually C major.

The French Augmented Sixth

The French augmented sixth (F6) is built on the raised sixth scale degree of the dominant scale, typically creating a rich, dissonant chord that resolves nicely to the tonic major chord.

Building the Chord

To create a French augmented sixth chord, start with the scale of the dominant major key. In C major, the dominant is G major. From the G major scale, construct a chord on the raised sixth degree:

The French augmented sixth chord in G major would be B-D-F#-A (an augmented triad over a sixth degree).

So, when playing B major with D and F# (with A as an added note), you get a B augmented sixth chord.

Harmonic Function

The F6 chord usually resolves strongly to the tonic major chord, adding a dramatic flair:

• Reinforces the tonic major chord (T).
• Creates a leading-tone dissonance that wants to resolve.
• Enhances the tension before the final tonic resolution.

In C major, the sequence might be B (F6) to E (ii) to C major (I).

Practical Application

Here’s an example in a C major context:

This sequence adds a beautiful dissonance that resolves beautifully to C major, giving your music a rich, intricate sound.

The Italian Augmented Sixth

The Italian augmented sixth (I6) is a chord built on the raised fourth scale degree of the relative minor scale. It is another intriguing chord that leads smoothly to the dominant minor chord.

Building the Chord

To build an Italian augmented sixth chord, first, identify the relative minor scale. In C major, this would be A minor. From the A minor scale, construct a chord on the raised fourth degree:

The Italian augmented sixth chord in A minor would be E major with an added fourth (C):

E major with the added fourth (C) gives us the notes: E, G#, B, C, F#, A.

Harmonic Function

The I6 chord serves several key functions:

• Leading to the dominant minor chord.
• Adding a sense of tension that resolves naturally to the dominant minor.
• Creating an unexpected and elegant harmonic progression.

In C major, an example could be Am to E-diminished to C major.

Practical Application

Let’s see an application in a C major context:

The E major chord with the added fourth creates a beautiful tension that resolves to A minor, and eventually to C major.

The German Augmented Sixth

The German augmented sixth (G6) is built on the lowered third scale degree of the relative minor scale. This chord creates a compelling dissonance that resolves to the subdominant major chord.

Building the Chord

To build a German augmented sixth chord, start with the relative minor scale of the key you are in. In C major, this is A minor. From the A minor scale, construct a chord on the lowered third degree: