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Introduction

This tutorial will look at what inversions are, how we create them for the seventh chords and how we know what inversion a particular chord voicing is. We will also look at two methods by which we can notate and identify seventh chord inversions.

What is a seventh chord?

In the tutorial on seventh chords, we discussed the construction of the most common seventh chords using stacked thirds so we should be clear on what a seventh chord is.

This stacking of three thirds results in intervals from the root of

• Root – 1
• Third – 3
• Fifth – 5
• Seventh – 7

Depending upon the quality of triad we have, major, minor, diminished, or augmented, and that of the seventh note, the quality of these intervals will be different, but for the purpose of looking at inversions we will just need to consider the numerical value of the interval, not the quality.

What is an inversion?

A discussed in the tutorial on triad inversions an inversion of chord is the same notes of the chord arranged in a different order, or more specifically with a different note as the bass. We only use the existing notes of the chord.

Since there are four notes in a seventh chord there are four different inversions available to us. We call these four different arrangements of the pitches

• Root position
• First inversion
• Second inversion
• Third inversion

We have our four distinct pitches that define our seventh chord. For example, a C dominant seventh chord

Root – C

Major third – E

Perfect fifth – G

Minor seventh – Bb

When the bass note, the lowest pitch of the triad, is the root note the triad is said to be a root position seventh chord. When the third is the bass note the chord triad is said to be a first inversion, if the fifth is in the bass we have a second inversion chord, and if the seventh is in the bass we have a third inversion seventh chord.

This same process applies to all the seventh chords as discussed in the earlier tutorial on the construction of the seventh chords.

The following table indicates the inversion, note order, and intervals above the root note, not the same as the bass note, for the C dominant seventh chord.

The four inversions of the C dominant seventh chord can be seen on the manuscript below.

It is important to note that the order of the upper notes does not change the inversion, it is only which note is present in the bass.

The inversion is defined by which note occupies the bass.

Why use inversions with seventh chords?

Inversions can impart a different sound to the same seventh chord

• Root position – Stable, full, centered
• First inversion – Warm, blended, softer
• Second inversion – Open, suspended, floating
• Third inversion – Tense, leaning, urgent

Here is a summary table of this information

Afterword

If you wish to learn more about how inversions and how they are identified using slash chord notation or figured bass notation, then please consider subscribing to the silver membership package where a more complete tutorial will be available alongside a downloadable pdf of the tutorial for reference.