To write a second inversion chord, you place the fifth of the chord in the bass, with the root and third appearing somewhere above it. This arrangement fundamentally defines a second inversion.
Understanding Chord Inversions
An inversion occurs when any note other than the root of a chord is in the bass (the lowest-sounding note). Chords can be inverted to create smoother bass lines, add variety, or achieve specific harmonic effects.
- Root Position: The root of the chord is in the bass.
- First Inversion: The third of the chord is in the bass.
- Second Inversion: The fifth of the chord is in the bass.
- Third Inversion (for seventh chords): The seventh of the chord is in the bass.
Characteristics of a Second Inversion Chord
A second inversion chord is characterized by having the fifth scale degree of the chord in the bass. The root and third of the chord are then placed above this bass note.
For example, if you're writing a C major triad (C-E-G):
- The root is C.
- The third is E.
- The fifth is G.
To write it in second inversion, the G (the fifth) would be the lowest note. The remaining notes (C and E) would be placed above it.
This means a second inversion chord for a triad is spelled (from bottom to top) either 5 - 1 - 3 or 5 - 3 - 1. For a seventh chord, the fifth is still in the bass, with the root, third, and seventh arranged above it.
Figured Bass Notation for Second Inversion
In music theory, figured bass is a shorthand notation used to indicate chord inversions and voicings above a given bass note.
- Triads in Second Inversion: Are typically indicated by the figures 6/4. This refers to the intervals of a sixth and a fourth above the bass note.
- Seventh Chords in Second Inversion: Are typically indicated by the figures 4/2 (or sometimes 2 or 4/3, depending on the specific seventh chord and context). This indicates a fourth, a second, and a third above the bass note, though often simplified.
| Chord Type | Figured Bass | Interval Relationship Above Bass | Example (C Major Triad) | Example (G7 Chord) |
|---|---|---|---|---|
| Triad | 6/4 | 6th and 4th | G - C - E | N/A |
| Seventh Chord | 4/2 (or 4/3) | 4th, 2nd, and 3rd | N/A | D - G - B - F |
Writing a Second Inversion Triad: Step-by-Step
Let's use a C major triad (C-E-G) as an example.
-
Identify the Root, Third, and Fifth:
- Root: C
- Third: E
- Fifth: G
-
Place the Fifth in the Bass: The note G becomes the lowest note of your chord.
-
Arrange the Remaining Notes (Root and Third) Above: Place C and E above the G.
Possible voicings (from bottom to top):
- G - C - E (fifth, root, third)
- G - E - C (fifth, third, root)
Both of these voicings are valid second inversions of a C major triad.
Writing a Second Inversion Seventh Chord: Step-by-Step
Let's use a G dominant seventh chord (G-B-D-F) as an example.
-
Identify the Root, Third, Fifth, and Seventh:
- Root: G
- Third: B
- Fifth: D
- Seventh: F
-
Place the Fifth in the Bass: The note D becomes the lowest note of your chord.
-
Arrange the Remaining Notes (Root, Third, Seventh) Above: Place G, B, and F above the D.
Possible voicings (from bottom to top):
- D - G - B - F (fifth, root, third, seventh)
- D - G - F - B (fifth, root, seventh, third)
- D - B - G - F (fifth, third, root, seventh)
- And so on, as long as D is the lowest note.
Common Uses and Contexts
Second inversion chords, particularly the 6/4 triad, have specific harmonic functions and are not used as freely as root position or first inversion chords due to their inherent instability.
Common categories of 6/4 chords include:
Cadential 6/4
This is the most common and important use. It typically occurs at a cadence, preceding a dominant chord (V) that then resolves to the tonic (I). It functions as an elaboration of the dominant chord. For instance, in C major, a I6/4 (G-C-E) would move to a V7 (G-B-D-F) and then to a I (C-E-G).
Passing 6/4
A passing 6/4 connects a root position chord to its first inversion (or vice-versa) with a stepwise bass line. For example, a I chord (C-E-G) might move to a V6/4 (D-G-B) as the bass moves C-D-E, resolving to a I6 (E-G-C).
Pedal 6/4
In a pedal 6/4, the bass note stays the same while the upper voices move to create a 6/4 chord temporarily. The bass note is often the dominant. For example, a C major chord (C-E-G) might move to a G6/4 (G-C-E) with the bass staying on G, and then resolve back to C major.
For more detailed information on figured bass and chord inversions, you can explore resources like Music Theory Fundamentals.
Practical Voicing Tips
When writing second inversion chords:
- Consider Voice Leading: Ensure smooth transitions between chords by moving individual voices (soprano, alto, tenor, bass) stepwise or by small leaps.
- Avoid Parallel Octaves and Fifths: These are generally considered undesirable in traditional four-part harmony.
- Maintain Balance: Distribute the notes across the voices to create a balanced sound, avoiding excessively wide or narrow spacing.
By understanding the structural definition and common applications, you can effectively write and utilize second inversion chords in your compositions.
