Harmonic analysis: tonal functions, cadences, modulations, chord identification and figured bass
What this domain tests
The exam gives you a short tonal passage and expects Roman numerals with inversions, correctly named cadences, a defensible modulation reading and fluent handling of baix xifrat (figured bass). Accuracy of function matters more than listing every chord.
Tonal functions
- Tònica (T): I, vi, iii in major; i, VI, III in minor.
- Subdominant (SD): IV, ii (iv, ii° in minor).
- Dominant (D): V, vii°. In minor, V and vii° require the raised leading tone (sensible), which is why the accidental appears in the score.
- Secondary dominants: V/V, V/ii and so on; they intensify a function without leaving the key.
Cadences
- Autèntica: V-I. It is perfecta only when both chords are in root position and the soprano ends on the tonic; otherwise imperfecta.
- Plagal: IV-I. Semicadència: any chord to V, typically mid-phrase. Trencada (deceptive): V-vi.
Modulation
- Diatònica: through an acord pivot, a chord belonging to both keys but changing function (Dm is ii in C, v in G).
- Cromàtica: the new leading tone arrives as an accidental, often after a sequence.
- Enharmònica: a diminished seventh or augmented sixth is reinterpreted.
Figured bass conventions
Triads: blank = 5/3 (root position), 6 = first inversion, 6/4 = second inversion. Sevenths: 7, 6/5, 4/3, 4/2 (= 2). Figures give intervals above the bass, not above the root; accidentals written beside a figure alter that interval.
Worked example
The notes B-D-F-G appear with B in the bass, in a C major context. Reasoning: reorder into thirds - G-B-D-F - giving a dominant seventh on G; the F natural (not F sharp) keeps it inside C major. The bass is the third of the chord, so the figured bass is 6/5 and the Roman numeral V6/5, dominant function. If C-E-G follows, the phrase closes with an authentic cadence in C.
Traps that cost marks
- Calling every V-I "perfecta" while the soprano sits on the third or fifth.
- Forgetting the raised leading tone in minor, then mislabelling the chord.
- Reading a 6/4 chord as a root-position triad with an added sixth.
- Announcing a modulation on a single chromatic chord with no confirming cadence in the new key.
- Numbering figured-bass intervals above the root instead of above the bass note.