Getting Started
While the second-inversion, or 6/4, chord is most famously used to prepare a cadence, its role in music is far more versatile. Beyond its strong dominant function at phrase endings, the 6/4 chord frequently appears in other contexts as a product of smooth voice leading and melodic embellishment. This chapter explores three such non-functional 6/4 chords—the passing, pedal, and arpeggiated—which are generated by specific, predictable patterns of melodic motion.
What You Should Be Able to Do
Analyze and label passing, pedal (neighboring), and arpeggiated 6/4 chords using Roman numerals.
Describe the specific voice-leading patterns in the bass and upper voices that create each type of 6/4 chord.
Write four-part harmony passages containing these chords, applying correct voice-leading procedures for doubling and melodic motion.
Identify voice-leading errors in notated examples featuring these non-functional 6/4 chords.
Aurally distinguish between the different types of 6/4 chords by listening for the characteristic bass motion of each.
Key Concepts & Analysis
The passing, pedal, and arpeggiated 6/4 chords are best understood not as independent harmonies but as byproducts of linear voice-leading patterns. Unlike the cadential 6/4, which has a strong harmonic function (as part of the dominant), these chords are contrapuntal in nature. Their identity is defined entirely by the melodic motion that creates them. They almost always occur on metrically weak beats, further signaling their role as embellishing or connecting chords rather than structural pillars.
The table below outlines the defining characteristics and voice-leading procedures for each type.
| Type of 6/4 Chord | Definition & Context | Voice-Leading Procedure |
|---|---|---|
| Passing 6/4 | Harmonizes the middle note of a three-note stepwise melodic figure in the bass. This bass note is a passing tone: a non-chord tone approached by step and resolved by step in the same direction. The chord serves as a linear bridge between two other chords. | The bass note, which is the fifth of the 6/4 chord, should be doubled. All upper voices should move by step, often in contrary motion to the bass to avoid parallel octaves and fifths. |
| Pedal (Neighboring) 6/4 | Embellishes a single, stationary harmony. The bass remains on the same note (acting as a pedal point) while the third and fifth of the chord are decorated by their upper neighbor tones: non-chord tones a step above a chord tone that resolve back down to the original note. | The bass note is held stationary. Two upper voices move up by step to their neighbors and then return to their original pitches. The resulting 6/4 chord is sandwiched between two instances of the same root-position chord. |
| Arpeggiated 6/4 | Created when the bass line outlines the notes of a single triad through arpeggiation (playing the notes of a chord one after another). This is not a change in harmony but simply a change of inversion over a sustained chord. | The three upper voices are held stationary, sustaining a single chord. The bass moves, arpeggiating the root, third, and fifth of that same chord. A common variant involves the bass oscillating between the root and fifth, as in a waltz. |
Data & Organization Tools
The identity of a non-functional 6/4 chord is determined by the melodic context, particularly the motion of the bass. This table summarizes the primary cues for identifying each type.
| 6/4 Type | Bass Motion | Upper Voice Motion | Typical Metrical Placement |
|---|---|---|---|
| Passing | Stepwise (e.g., C–D–E) | Stepwise | Weak Beat |
| Pedal | Stationary (e.g., C–C–C) | Neighboring (e.g., E–F–E) | Weak Beat |
| Arpeggiated | Arpeggiation (e.g., C–G–C) | Stationary | Varies |
Evidence Bank
Passing 6/4: A chord that harmonizes a bass passing tone, such as the V6/4 in the progression I–V6/4–I6. It creates smooth, stepwise bass motion.
Pedal (Neighboring) 6/4: A chord that embellishes a static harmony, created by upper neighbor tones over a held bass note. A common example is I–IV6/4–I.
Arpeggiated 6/4: A change of inversion caused by the bass arpeggiating a triad while the upper voices sustain the same harmony, as in I–I6–I6/4.
Bass Passing Tone: A non-chord tone in the bass that is approached by step and left by step in the same direction. The passing 6/4 chord harmonizes this tone.
Upper Neighbor Tone: A non-chord tone located a step above a stable chord tone, which then resolves back down to the original note. This motion in two upper voices creates the pedal 6/4.
Stepwise Motion: The required melodic movement for all voices in a properly handled passing 6/4 chord.
Stationary Bass (Pedal Point): The defining feature of the pedal 6/4, where the bass note of the embellished chord is sustained through the 6/4 itself.
Doubling the Bass: The standard voice-leading procedure for the passing 6/4. Since the bass note is the chordal fifth, this is an exception to the general rule of doubling the root.
Skill Snapshots
Voice-Leading
Rule: In a passing 6/4 chord, the bass note (the chordal fifth) must be doubled.
- Effect: This doubling stabilizes the unstable 6/4 inversion and facilitates smooth, stepwise voice leading in all parts, preventing parallel perfect intervals.
Rule: In a pedal 6/4 chord, the bass is held stationary while two upper voices move to their upper neighbors and back.
- Effect: This procedure clarifies the chord's function as a simple embellishment, ensuring the listener perceives the passage as a prolongation of a single harmony rather than a true chord progression.
Rule: In an arpeggiated 6/4 chord, the three upper voices remain stationary.
- Effect: This makes it clear that the harmony is not changing. The listener perceives the motion as a melodic elaboration in the bass line, not a harmonic shift.
Common Misconceptions & Clarifications
Confusing all 6/4 chords with the cadential 6/4.
- Clarification: Passing, pedal, and arpeggiated 6/4 chords are products of voice leading, not harmonic function. Unlike the cadential 6/4, which prepares the dominant on a strong beat, these chords are embellishments that typically occur on weak beats.
Incorrectly doubling the root of a passing 6/4 chord.
- Clarification: The standard procedure for a passing 6/4 is to double the bass note, which is the fifth of the chord (e.g., in a V6/4, double scale degree ^2). This is a specific exception to general doubling rules and is necessary for correct voice leading.
Misidentifying the function of these chords.
- Clarification: These 6/4 chords do not have an independent harmonic function. For example, a V6/4 used as a passing chord in the progression I–V6/4–I6 does not function as a dominant. It is a linear, contrapuntal chord that connects two tonic harmonies.
Assuming the bass must arpeggiate a full triad for an arpeggiated 6/4.
- Clarification: The arpeggiated 6/4 can be created by a complete arpeggio (root-third-fifth) or by a simpler oscillation between two chord members, most commonly the root and fifth. This latter pattern is frequently found in accompaniment styles like the waltz.
Summary
Beyond the harmonically significant cadential 6/4, music employs three other types of 6/4 chords that arise from contrapuntal motion: the passing, pedal (or neighboring), and arpeggiated 6/4. These chords are not defined by harmonic function but by the specific voice-leading patterns that create them. The passing 6/4 harmonizes a stepwise bass line, connecting two other chords. The pedal 6/4 embellishes a single, static harmony through the use of upper neighbor tones over a stationary bass. The arpeggiated 6/4 is the result of the bass outlining the notes of a triad beneath stationary upper voices. Correctly identifying, analyzing, and writing these chords requires a focus on the melodic context, particularly the motion of the bass.