7/9 7. Introduction to Voice Leading

The Four-Part Texture

Voice leading treats a chord as more than a group of simultaneous pitches: each pitch belongs to an independent musical line. In a standard four-part texture, the parts are soprano, alto, tenor, and bass.

The voices normally remain in the order

The soprano is the highest part and often carries the most prominent melody. The alto and tenor are inner voices, while the bass provides the lowest line and often supports the harmonic foundation.

A triad has three pitch classes, but four parts require four notes, so one chord member is usually doubled. In a root-position triad, doubling the root commonly reinforces the chord's identity. Doubling a third or an unstable scale degree requires more care.

A useful first principle is to serve two goals at once:

• Make the harmony recognizable.

• Give each voice a natural, singable line.

Takeaway: Write independent parts that collectively express a clear chord progression.

Spacing and Smooth Connections

Good Spacing supports clarity in the lower register and cohesion in the upper register. Keep the soprano and alto within an octave when possible, and do the same for the alto and tenor. The tenor and bass may be separated by more than an octave.

Judge spacing between neighboring voices:

• Soprano to alto

• Alto to tenor

• Tenor to bass

In close spacing, the upper voices fit within an octave. In open spacing, a larger gap appears between some adjacent upper voices. Either approach can work if the voices remain in order, singable, and free from awkward overlap.

When connecting two chords, first identify pitches that both chords share. Retaining a shared pitch in the same voice creates a Common tone and therefore no melodic motion. For example, C-major and A-minor triads share $C$ and $E$, so one voice can retain $C$ while another retains $E$.

If no common tone is available, prefer the smallest reasonable motion:

1. No motion for a common tone.

2. A half step or whole step.

3. A third.

4. A larger leap only when the harmony or melody requires it.

Leaps are often most convincing when they occur within a chord or are balanced by stepwise motion in the opposite direction. Smoothness does not require every voice to move by step.

Takeaway: Retain common tones when practical, then use the smallest useful motion while preserving spacing and voice independence.

Tendency Tones and Resolution

Active pitches need special attention. The Tendency tone most commonly discussed in tonal music is the leading tone, scale degree $\hat{7}$, which normally resolves upward by semitone to tonic, scale degree $\hat{1}$. In C major, this is $B \rightarrow C$. When a leading tone occurs in a dominant-function chord such as $V$ or $\mathrm{vii}^{\circ}$, its upward pull is especially important.

A Chordal seventh normally resolves downward by step. In a G-seventh sonority leading to C major, $F$ is the chordal seventh and normally moves to $E$:

Sometimes the leading tone and chordal seventh cannot both follow their usual resolutions without creating another problem. In that situation, the stylistic context determines the best controlled exception. Such alternatives should be considered after the normal resolutions have been tested.

A typical $V$-to-$I$ connection in C major can preserve $G$ as a common tone, move $D$ upward to $E$, resolve $B$ upward to $C$, and move the bass from $G$ to $C$. This combination gives the progression a clear dominant-to-tonic pull while keeping several lines smooth.

Takeaway: Resolve active notes deliberately: the leading tone normally rises, and a chordal seventh normally falls.

Motion and Independence

Two voices moving together can create problems when they form perfect intervals. Parallel fifths and Parallel octaves are avoided because they can make two parts sound like one merged line.

To check a connection, inspect every pair of voices:

• Soprano-alto

• Soprano-tenor

• Soprano-bass

• Alto-tenor

• Alto-bass

• Tenor-bass

For each pair, compare the interval before and after the change. Then ask whether both voices move in the same direction and whether the two intervals are perfect fifths or perfect octaves. If so, revise the connection.

Direct, or hidden, fifths and octaves also deserve caution. They occur when voices move in the same direction into a perfect fifth or octave even though the preceding interval was not perfect. These are especially carefully treated when the soprano and bass are involved.

Motion can be classified in several ways:

• Similar motion: both voices move in the same direction by different intervals.

• Parallel motion: both voices move in the same direction by equivalent intervals while preserving the same interval type.

• Contrary motion: one voice rises while the other falls.

• Oblique motion: one voice moves while the other remains on the same pitch.

• Static motion: both voices retain their pitches.

Common tones create oblique or static motion, while contrary motion often helps maintain independence.

Takeaway: Check all six voice pairs, not just the soprano and bass, and prefer contrary or oblique motion when it helps avoid perfect-interval problems.

A Practical SATB Writing Procedure

A reliable workflow reduces errors when connecting two chords.

1. Write the bass. The bass establishes the harmonic foundation and often determines the inversion.

2. Shape or inspect the soprano. Preserve a given soprano; otherwise, choose a singable line with a clear contour.

3. Mark common tones. Retain shared pitches in the same voices whenever this does not create a spacing or resolution problem.

4. Resolve tendency tones. Check leading tones, chordal sevenths, suspensions, and other active notes.

5. Complete the inner voices. Supply missing chord members, choose appropriate doubling, and favor stepwise or common-tone motion.

6. Perform a final check. Confirm the chord members, spacing, voice order, resolutions, melodic leaps, doubling, and perfect-interval motion.

For example, when moving from $\mathrm{ii}^{6}$ to $V$ in C major, $D$ is a common tone, $F$ in the bass can move to $G$, and $A$ can move to $G$ or $B$ depending on the voicing. The actual voice parts must be evaluated; naming the chord roots alone is not enough.

When an error appears, revise the smallest part of the texture that solves it. A parallel fifth may be repaired by keeping one voice stationary, reversing one voice's direction, or assigning a different chord member to one part. An unresolved leading tone should usually be moved upward to tonic, and an unstable doubled tone should often be replaced by a stable chord member.

Final checklist:

• Are all required chord members present?

• Is the order soprano-alto-tenor-bass preserved?

• Are the upper adjacent voices within an octave when appropriate?

• Are common tones retained where useful?

• Do leading tones and chordal sevenths resolve normally?

• Are parallel and problematic direct fifths or octaves absent?

• Are leaps singable and balanced?

• Is doubling appropriate for the chord?

Takeaway: Establish the bass, shape the soprano, retain common tones, resolve active notes, complete the inner voices, and then inspect the entire texture.

• Voice crossing

• Voice overlap