Notes on Chapter 13: Dominant Sevenths and Predominant Area

Expanding the Basic Phrase: T-PD-D-T

  • Chord Progression: Focus on the predominant (PD) area before the dominant (D).

  • Predominant Chords: Subdominant triad (IV) and supertonic triad (ii) lead to the dominant (V or V7).

Key Concepts

  • Predominant Harmonies: ii and IV are crucial as they lead to the dominant.

  • Phrase Model: T-PD-D-T is common, where:

    • Major: I (T) → IV/ii (PD) → V/V7 (D) → I (T)

    • Minor: i (T) → iv/ii° (PD) → V/V7 (D) → i (T)

  • Root Movement: Strong predominants often move in descending thirds (IV to ii).

Voice Leading from Predominant to Dominant

  • Voice Leading: Move upper voices in contrary motion to bass when transitioning from PD to D.

  • Chordal Seventh: Should be prepared by common tone or step, resolves down.

Predominant Seventh Chords

  • Usage: Predominant sevenths (e.g., ii7) in four-part writing should be complete and well-prepared.

  • Dissonance Treatment: The chordal seventh must resolve properly.

Figured Bass Realization

  • Expectation for performers to improvise harmonies from given bass lines (figured bass).

  • Importance of knowing common progressions based on T-PD-D-T for effective composition and harmonization.

Chord Progression: Focus on the predominant (PD) area before the dominant (D), establishing a strong harmonic foundation that enhances the resolution to the tonic (T).

Predominant Chords: The two primary predominant chords are the subdominant triad (IV) and the supertonic triad (ii). These chords effectively lead to the dominant (V or V7) by creating a pull towards resolution, often used in various genres of music.

Key Concepts

Predominant Harmonies: Chords ii and IV are crucial as they set up a harmonic tension that prepares the listener for the dominant and eventual tonic resolution. Their strategic use is common in both classical and popular music.

Phrase Model: The T-PD-D-T progression is a foundational concept in Western tonal music, where:

  • Major: I (T) → IV/ii (PD) → V/V7 (D) → I (T)

  • Minor: i (T) → iv/ii° (PD) → V/V7 (D) → i (T)
    This structure not only governs the flow of harmonies but also influences melody writing, ensuring a cohesive musical narrative.

Root Movement: Strong predominants typically move in descending intervals, particularly thirds (from IV to ii), which create a smooth bass line and maintain musical coherence. This movement reinforces the harmonic direction and emotional aspect of the progression.

Voice Leading from Predominant to Dominant

Voice Leading: As upper voices transition from the PD to the D, it is essential to employ contrary motion to the bass. This technique enriches the harmonic texture and facilitates smoother voice movement.

Chordal Seventh: When using seventh chords, the chordal seventh should be prepared either by common tone or step, resolving down to the root of the next chord for effective resolution and to maintain harmonic clarity.

Predominant Seventh Chords

Usage: When predominants such as ii7 are employed in four-part writing, they should be voiced fully and thoroughly prepared, ensuring all parts contribute to the overall harmony and texture.

Dissonance Treatment: Proper treatment of dissonance is crucial; the seventh must resolve appropriately to enhance the harmonic progression and maintain the listener's sense of direction.

Figured Bass Realization

Expectation for performers: Musicians are expected to improvise harmonies based on the given bass lines (figured bass). This skill is essential for enhancing accompaniment and enriching melodic lines.

Importance of knowing common progressions: Understanding common progressions based on T-PD-D-T is vital for effective composition and harmonization, enabling musicians to create compelling, cohesive musical works across various styles.