Harmonic and contrapuntal techniques: functional progressions, cadences, modulation, voice-leading, four-part writing, suspensions, sequences, imitation, canon and the principles of counterpoint.

What this dot point is asking

These are the technical craft skills behind Component 3, especially the Western classical brief. AQA wants you to write convincing functional harmony with good voice-leading, handle cadences and modulation, and use contrapuntal devices such as suspensions, sequences, imitation and canon when composing.

Functional harmony

Voice-leading and four-part writing

In four-part (SATB) writing, keep each voice in range, double the root of root-position chords by preference, and move the parts smoothly between chords. The conventional ranges are roughly soprano $c'$ to $g''$, alto $g$ to $d''$, tenor $c$ to $g'$ and bass $E$ to $d'$, and adjacent upper voices (soprano, alto, tenor) should stay within an octave of each other to avoid gaps. Prefer contrary or oblique motion between the outer parts, because similar motion in all voices is what produces the consecutive fifths and octaves that the mark scheme penalises. Move to the nearest available chord note, keep common tones in the same voice where possible, and let the leading note rise to the tonic at perfect and imperfect cadences (especially when it is in the soprano). At a dominant seventh chord, resolve the seventh down by step and the third (the leading note) up by step, which automatically gives correct voice-leading into the tonic.

Modulation in practice

Modulation gives a longer piece tonal architecture, and examiners reward modulations that are prepared rather than abrupt. The standard method is the pivot chord: find a chord common to both the old and new keys, reinterpret it in the new key, then confirm the arrival with a perfect cadence in that key. A move from C major to G major might pivot on the chord of A minor (vi in C, ii in G) before a $V$ to $I$ cadence in G. The most idiomatic destinations are closely related keys: the dominant, the subdominant, the relative minor or major, and (in minor keys) the relative major. Secondary dominants ($V$ of $V$, for instance the chord of D major pushing toward G in C major) are a quick way to tonicise a new key for a phrase or two without a full modulation. A typical tonal plan for a brief composition is tonic, dominant, return to tonic, with perhaps a touch of the relative minor for contrast.

Counterpoint

Counterpoint combines two or more independent melodic lines that are interesting in themselves yet combine into correct harmony. The key devices each have a precise meaning: imitation (one part states an idea and another echoes it shortly after, often at a different pitch), canon (strict imitation maintained throughout, as in a round), inversion (the imitating line turns the intervals upside down), suspension (a note held over from the previous chord clashes, then resolves down by step), and sequence (a melodic and harmonic pattern repeated at successively higher or lower pitches). The guiding principle is independence with agreement: each line should have its own contour and rhythm, but consonances should fall on strong beats and any dissonance should be prepared and resolved. A pedal point (a sustained tonic or dominant under moving upper parts) is another device that anchors a contrapuntal passage.