Getting Started
Building upon your knowledge of diatonic triads, this section introduces seventh chords, which add a fourth note and a new layer of dissonance to the harmonic palette. Mastering the voice-leading procedures for these chords is crucial for creating smooth, coherent, and stylistically convincing four-part textures. The principles you learn here govern how tension is created and resolved in tonal music.
What You Should Be Able to Do
Identify the chordal seventh in any seventh chord and its inversion.
Apply the correct resolution procedure for a chordal seventh in a four-voice texture.
Write a complete or incomplete root-position dominant seventh chord according to voice-leading principles.
Analyze musical scores to identify correct and incorrect handling of chordal sevenths.
Realize a figured bass or Roman numeral progression involving seventh chords in four parts.
Key Concepts & Analysis
The introduction of a seventh to a chord creates a dissonance that requires careful handling. The primary focus of voice leading with seventh chords is the preparation and, most importantly, the resolution of this dissonant tone.
The Chordal Seventh and Its Resolution
A chordal seventh is the note located a diatonic seventh above the root of a chord. In a V7 chord in C major (G-B-D-F), the note F is the chordal seventh. This interval is considered a dissonance in the common-practice style and has a strong melodic tendency.
The fundamental rule for handling this dissonance is straightforward:
- Normative Resolution: All chordal sevenths must resolve by a descending step in the same voice.
This downward stepwise motion smoothly resolves the harmonic tension into a consonance in the subsequent chord. For example, in a V7-I progression in C major, the chordal seventh F (^4) in the V7 chord will resolve down by step to E (^3) in the I chord. A failure to resolve the seventh in this manner is considered a significant voice-leading error, often called an unresolved seventh.
Writing Root-Position Seventh Chords
When writing a dominant seventh chord (V7) in root position, you have two options, both of which are stylistically correct. The choice depends on which option allows for the smoothest voice leading.
Complete V7 Chord: The chord contains all four members: root, third, fifth, and seventh. In four-part writing, this means no notes are doubled. While common, writing a complete V7 resolving to a complete I can sometimes create voice-leading problems, such as parallel fifths.
Incomplete V7 Chord: The fifth of the chord is omitted, and the root is doubled. This is a very common and useful technique to avoid voice-leading errors. By omitting the fifth, you eliminate the potential for parallel fifths between the fifth of the V7 and the root of the I chord. The doubled root reinforces the chord's identity.
Writing Inverted Seventh Chords
Unlike root-position V7 chords, inverted seventh chords have a strict requirement for their spelling in four-part writing.
- All inverted seventh chords must be spelled completely. This means that first inversion (V6/5), second inversion (V4/3), and third inversion (V4/2) chords must always contain the root, third, fifth, and seventh. No notes may be omitted or doubled. This ensures the full sonority and function of these less stable chords are clearly communicated.
A Special Case: The V4/3 Chord
There is one specific and important exception to the downward resolution rule for chordal sevenths.
- In a I - V4/3 - I6 progression, the chordal seventh (which is in the bass voice of the V4/3 chord) may resolve by an ascending step.
For example, in C major, this progression would be C - G4/3 - C6. The bass line would move from C (^1) up to D (^2) and then up to E (^3). Here, the D in the bass of the V4/3 is the chordal seventh of the G7 chord. Instead of resolving down to C, it moves up to E. This creates a smooth, stepwise bass line and is a common contrapuntal pattern. This exception applies only to this specific harmonic context.
Data & Organization Tools
This table summarizes the essential voice-leading conventions for dominant seventh chords in a four-voice texture.
| Chord Type | Spelling | Doubling & Omission | Seventh Resolution |
|---|---|---|---|
| Root-Position V7 | Complete (R, 3, 5, 7) | No doubling or omission. | Down by step. |
| Root-Position V7 | Incomplete (R, R, 3, 7) | Fifth is omitted; root is doubled. | Down by step. |
| First Inversion V6/5 | Complete (R, 3, 5, 7) | Must be complete. | Down by step. |
| Second Inversion V4/3 | Complete (R, 3, 5, 7) | Must be complete. | Down by step (or up in I-V4/3-I6). |
| Third Inversion V4/2 | Complete (R, 3, 5, 7) | Must be complete. | Down by step. |
Evidence Bank
Chordal Seventh: The dissonant note that is a seventh above the root of a chord. It requires resolution.
Descending Stepwise Resolution: The standard and required procedure for resolving a chordal seventh. The voice containing the seventh must move down by a step into the next chord.
Unresolved Seventh: A voice-leading error that occurs when the chordal seventh is left by leap, remains on the same note, or resolves incorrectly.
Incomplete Dominant Seventh: A root-position V7 chord where the fifth is omitted and the root is doubled. This is a common strategy to achieve smooth voice leading.
Complete Seventh Chord: A seventh chord that contains all four of its members (root, third, fifth, seventh). All inverted seventh chords must be complete.
The I - V4/3 - I6 Progression: A specific harmonic pattern where the chordal seventh in the V4/3 chord is permitted to resolve up by step to create a smooth bass line.
Skill Snapshots
Voice-Leading Rule: The chordal seventh resolves down by step.
- Effect: This resolves the chord's primary dissonance smoothly into a consonance in the following chord, creating a satisfying sense of release and melodic coherence.
Voice-Leading Rule: Omit the fifth and double the root in a root-position V7 chord.
- Effect: This often simplifies the voice leading when moving to a I chord, helping to avoid parallel fifths and octaves while allowing the leading tone to resolve correctly to the tonic.
Voice-Leading Rule: All inverted seventh chords must be complete.
- Effect: This ensures the full sonority and function of the chord is heard. Because inversions are inherently less stable than root position, the presence of all tones is necessary to define their sound and harmonic role.
Common Misconceptions & Clarifications
Misconception: The chordal seventh can be left by a leap if the line sounds good.
- Clarification: In this style, the chordal seventh is a functional dissonance that must be resolved by step, almost always downwards. Leaping away from it is considered an error.
Misconception: You can omit the fifth in any seventh chord to make the writing easier.
- Clarification: Omitting the fifth is a technique used specifically for root-position dominant seventh chords. Inverted seventh chords must always be complete.
Misconception: The upward resolution of the seventh in a V4/3 is always an option.
- Clarification: The upward resolution of the chordal seventh is an exception that applies only within the specific I - V4/3 - I6 progression to facilitate a smooth, stepwise bass line. In all other harmonic contexts, it must resolve down.
Misconception: When a V7 is incomplete, you can double any available note.
- Clarification: In an incomplete root-position V7, the convention is to double the root of the chord. Doubling the third (the leading tone) or the seventh is incorrect.
Summary
Seventh chords introduce a functional dissonance—the chordal seventh—that must be handled with care in four-part writing. The foundational principle is that the chordal seventh must resolve down by step into the next chord. When writing a root-position dominant seventh (V7), composers may use a complete chord or an incomplete version (omitting the fifth and doubling the root) to facilitate smoother voice leading. However, all inverted seventh chords must be written as complete chords with all four members present. A notable exception to the resolution rule occurs in the I - V4/3 - I6 progression, where the bass voice (the chordal seventh) may ascend by step. Adherence to these conventions is essential for creating music that is stylistically authentic and logically constructed.