Reading the symbols in a chord progression is not simple—particularly if it consists of Roman numerals. However, understanding how to read chord inversion symbols is necessary. It is the key to understanding the function of the chords in a song.
Simple Roman numerals are simple enough, however, you might have gotten stuck on an unfamiliar chord with a strange subscript number stacked up like a fraction.
If that’s the case, you will need to learn your chord inversions and figured bass symbols to keep progressing.
In this article, I will go through everything you should know to understand and read chord inversion symbols and figured bass.
What’s figured bass?
Figured bass is how chord inversions are written in the Roman numeral analysis.
It is the small subscript numbers you might have seen underneath chord symbols in some sheet music.
However, hang on a second. Chord inversions? Roman numeral analysis?
First off, to know figured bass I will have to cover inverted chords.
What are chord inversions?
Inverted chords are chords whose notes appear in a different order than root position.
Here’s how it works. Basic chords are built by stacking triads on top of each other.
The interval relationships between the root and other notes determine the chord quality.
Case closed right? Not fairly. Not every single chord is written as a blocky snowman with the notes directly on top of each other.
Think about a chord that looks like this:
The way it’s written right now, you will not have only triads to evaluate—yet the chord still contains the same individual notes as your simple C major triad.
And if you listen to the notes played together they still sound out a C major chord.
The chord you are an inversion of C major. It’s still C main—however, the notes are arranged in a unique order.
When you rearrange them, you could rewrite the chord as the familiar basic triad.
Inversions are simply stacked third chords with their notes arranged in different orders.
However, changing the order can have an enormous impact on the sound.
Different notes in the uppermost or lowermost voice could give a basic chord a distinct feel.
And these inverted voicings permit for extra inventive voice main potentialities. Inversions are necessary!
First, second and third inversion
Triads could be written 3 ways.
Root position is the familiar snowman style with each third stacked directly on top of the last one.
First inversion starts on the first interval above the root.
Second inversion begins on the second interval above the root.
Seventh chords with their additional tone could be arranged in yet another inversion—third inversion.
Third inversion begins on the top note of the snowman, otherwise known as the seventh of the chord.
Now that I have covered the basics of inversions, I will take a look at these pesky subscript numbers.
They seem like fractions, however, they are anything but.
Instead, figured bass tells you that inversion a chord is in. The way it works could be confusing.
Look back at a basic triad. Rewritten in first inversion, it looks like this:
Evaluate the intervals of the inverted chord in relation to the bass voice—the lowermost note in the chord.
The note immediately above (the fifth of the chord) is a third above the bass voice. And the top note (the root) is a sixth above the bass.
These are the numbers that seem in the subscript below inverted chords. Figured bass shows the true interval relationships relative to the bass voice of the chord.
In practice, you do not want to show every single interval to represent the inversion. In proper figured bass, basic intervals are generally omitted to make the symbols easier.
Here’s a list of inversions, intervals and the figured bass symbols that represent them.
Inversions with figured bass in practice
All this theory is good on paper, however, it’s no use unless you could hear it in context with real music.
I will go back to an example from our article on emotional chord progressions.
Some readers were confused by the descending minor progression utilized in The Beatles “While My Guitar Gently Weeps.”
I’ll break it down:
There are two inversions present in this progression. The second chord in the cycle is written with the figured bass marking 4 2.
When you refer back to the chart, which means it’s a seventh chord written in third inversion.
You could see this in the chord symbol below. The slash indicates that G (the seventh of Amin7) must be performed within the lowest voice of the chord.
The following chord is written with the figured bass marking 6. Which means it’s a triad in first inversion. Once again, the chord symbol uses a slash to show that the third of the D major chord needs to be played in the lowest voice.
That is all it takes to read inversions on a chord chart!
Hot tip: By inverting the chords, this progression cleverly preserves smooth downward stepwise motion in the bass voice. That is the power of inversions—and good voice leading!
Chord inversions and figured bass are important for proper Roman numeral analysis.
With these key to read chord inversion symbols under your belt, you will discover a lot more harmonic possibilities out there to discover!