In C minor, a chord appears with F in the bass, Ab in the middle, and Db on top. A student labels it as a diminished seventh chord and moves on. What is the correct analysis?
AIt is a French augmented sixth chord in first inversion
BIt is the Neapolitan sixth (N6) — a Db major chord in first inversion — functioning as a pre-dominant
CIt is an enharmonic respelling of the leading-tone diminished seventh chord
DIt is a borrowed iv chord from Db major
The chord F–Ab–Db is Db major in first inversion — scale degree 4 (F) is in the bass, with the root (Db, the flattened second) above. This is the Neapolitan sixth chord (N6 or bII6). It is not diminished (Db major is a perfectly consonant major triad), and it is not an augmented sixth chord (which contains a specific augmented sixth interval). Its function is pre-dominant: it typically progresses to V, substituting for ii or IV with greater harmonic color and tension.
Question 2 Multiple Choice
A piece in C minor reaches N6. Which of the following progressions represents the most characteristic resolution?
AN6 → i (Neapolitan resolves directly to tonic for a deceptive effect)
BN6 → VI (Neapolitan moves to the submediant as a half-cadence substitute)
CN6 → V (Neapolitan resolves to dominant as a pre-dominant chord)
DN6 → iv (Neapolitan returns to the subdominant to prolong the pre-dominant area)
The Neapolitan chord's primary function is pre-dominant: it builds tension in preparation for the dominant. The characteristic progression is N6 → V or N6 → V7 → i. The bass note of N6 — scale degree 4 (F in C minor) — moves up by step to scale degree 5 (G), exactly as the bass of a first-inversion ii chord would. Meanwhile, the chord's root (Db) typically resolves downward by augmented second to the leading tone (B natural), giving the resolution its distinctive expressive weight.
Question 3 True / False
In the Neapolitan sixth chord (N6), the bass note is the flattened second scale degree (the root of bII), which moves down by step to the dominant.
TTrue
FFalse
Answer: False
False. The Neapolitan almost always appears in first inversion, which means the bass note is scale degree 4 (the third of the chord), not the root (the flattened second). In C minor, the bass is F (scale degree 4), not Db (the root, bII). This bass note moves UP by step to G (scale degree 5, the dominant bass) — not down. The flattened second (Db) appears in an upper voice and resolves downward, often by an augmented second, to the leading tone.
Question 4 True / False
The Neapolitan chord appears in both major and minor keys, but it is most common in minor-key music because the minor mode's already-darkened sound makes the chromatic Neapolitan less disruptive.
TTrue
FFalse
Answer: True
True. While the Neapolitan can appear in major keys (requiring extra accidentals), it is far more idiomatic in minor, where the lowered scale degrees already create a darker harmonic environment. In C minor, Db is relatively close to the existing Eb and Ab of the natural minor scale; in C major, Db is a more jarring intrusion. The Neapolitan's somber, dramatic quality blends with the emotional character of minor-key music, which is why Baroque and Classical composers (especially in minor-key arias and sonata movements) reached for it most frequently.
Question 5 Short Answer
Why does the Neapolitan chord almost always appear in first inversion rather than root position, and what specific voice-leading motion does this inversion enable?
Think about your answer, then reveal below.
Model answer: First inversion places scale degree 4 in the bass, which then moves smoothly up by step to scale degree 5 (the dominant bass) when N6 resolves to V. This stepwise bass motion provides smooth voice leading. Root position (with the flattened second in the bass) would require the bass to leap a diminished third or augmented sixth to reach the dominant, creating awkward voice leading. First inversion also avoids doubling the root (bII), whose strong chromatic tendency makes it difficult to double without parallel motion problems.
The practical result is that N6 behaves like a first-inversion pre-dominant chord (similar to ii6 in root position): bass on scale degree 4 moving to 5, while the root in an upper voice leaps or steps to the leading tone. This inversion is so standard that the '6' in 'N6' is part of the label itself — the Neapolitan in first inversion is the default form, and the label 'N' without '6' usually implies the same thing.