Seventh chords feature an additional note stacked atop of their triad to give them their name: it is known as a chordal seventh and must resolve to its following chord by moving back down by one step.
Seventh chords can also have various inversions, which are indicated by numbers placed above their chord symbol in figured bass notation. We will discuss three primary inversions of seventh chords:
Root position
One of the key takeaways when it comes to seventh chords is understanding that their roots don’t have to be the lowest-sounding note; indeed, you could arrange one so that its bass note actually sits higher than any of its other tones!
This arrangement is known as first inversion. To be specific, a root-position seventh chord may contain dominant seventh chords, subdominant seventh chords or even half-diminished seventh chords.
Listening closely is key when it comes to recognizing seventh chord inversions; simply listen for any gaps between bass note and root. With practice, you should soon be able to identify all the various seventh chord inversions by ear! I have created a helpful flow chart which illustrates all these various inversions as they relate to one another as well as how you can form complete chord structures from their individual components.
First inversion
When seventh chords appear in their initial inversion, they usually resolve by an ascending fifth (or falling fourth) root motion, leading to sonorities with roots one fifth below or above their own roots; for instance, ii6/5 will usually lead to V in its resolution.
As such, seventh chord symbols should appear before Roman numerals and after triad chord numbers for easy recognition by ear provided that you possess an understanding of intervals.
To determine an inversion of a seventh chord, look at its bass note and compare it to notes in the scale above it. For instance, the root note of a C major seventh chord is B; accordingly, its bass note would be F in an I7 chord; after this process is complete, upper notes can be stacked freely as desired.
Second inversion
As with triads, seventh chords also feature inversions. A common inversion for dominant seventh chords, though it can also be applied to tonic and subdominant chords.
Practice is crucial when it comes to recognizing inversions by ear, particularly for more complex chord structures. Start off by learning root position seventh chords before progressing through all inversions of seventh chords! Soon enough you’ll be able to identify seventh chords regardless of their inversion!
To assist in this endeavor, it’s crucial that you understand Roman numerals. Each number represents a chord; for instance, a tonic seventh chord would be 7, while its dominant seventh counterpart is 9. Other seventh chords may be classified diatonic or harmonic depending on their intervallic content – for instance a chord built upon scale degree 11 is uncommon within tonal music due to its dissonant seventh that would compromise its stability.
Third inversion
The third inversion of a seventh chord refers to an arrangement wherein the fifth note serves as the bass note and root is stacked above it. Although this type of inversion sounds dissonant and may be difficult to identify by ear at first, with practice you can develop your ability to recognize it easily.
When identifying seventh chord inversions by ear, it is essential to start from the root position and work your way upward. This allows you to focus on identifying intervals within each inversion and gain a good understanding of their qualities.
Noticing seventh chords requires keeping in mind that there are no numbers next to each chord like there are with triads. Instead, roman numerals indicate their inversion; I7 refers to diatonic seventh chord built on scale degree 11 while ii7 indicates diminished seventh built on scale degree 22.