Minor Key Harmony Fundamentals and Essential Chord Logic

How does the natural minor scale differ from the harmonic and melodic minor scales?

The natural minor scale contains a flat 7th degree, which creates a weak, modal cadence lacking a strong pull to the tonic. Conversely, the harmonic and melodic scales raise the 7th degree by a half-step to establish a leading tone, providing the 1 semitone distance necessary for definitive resolution.

What are the primary chords used in minor key progressions?

Standard minor key progressions rely heavily on the i, iv, and V chords. In A minor, this means using Am, Dm, and E major. These chords establish the tonal center and provide the necessary tension-release cycle that defines Western functional harmony. The V chord is particularly effective because its major third, the G#, acts as the leading tone to the tonic A.

A common nuance involves the use of the diminished ii° chord. While technically part of the diatonic set, it often sounds unstable and is frequently replaced by the iv chord or a iiø7 chord in jazz contexts. Writers should be aware that while the i-iv-V structure is the backbone, substituting these with seventh chords or extended voicings adds color without sacrificing the underlying functional pull of the progression.

What role does the raised seventh scale degree play in creating functional harmony?

The raised seventh degree creates a leading tone that pulls upward to the tonic by a single semitone, effectively defining the boundary of the key. Many assume that the raised seventh must be present in every chord of a minor progression, but this is a mistake. It is only required when the harmony moves toward the tonic. Using the raised seventh in chords that do not function as a dominant can create awkward, jarring intervals, such as an augmented second, which disrupts the flow of the melody.

How are secondary dominants utilized within a minor key context?

Secondary dominants function by temporarily tonicizing a chord other than the tonic, typically by preceding it with its own dominant chord.

• V/iv creates a strong push toward the subdominant by using the major dominant of the iv chord.
• V/V introduces the secondary dominant of the dominant, often utilizing a raised 4th degree to pull toward the V chord.
• V/III helps establish the relative major as a temporary tonal center, adding harmonic variety.
• V/vi is less common in minor, but it provides a sharp, chromatic color when moving toward the sixth degree of the scale.

What is the function of the subdominant minor chord in minor key compositions?

The subdominant minor (iv) chord provides a distinct, melancholic color that distinguishes minor keys from their major counterparts. By lowering the sixth scale degree, composers create a smooth, descending chromatic line that contrasts sharply with the sharp, upward pull of the V chord. In C minor, this involves moving from the F minor chord to the G major chord, creating a powerful emotional shift that feels both settled and yearning.

An important exception occurs when the iv chord is voiced with a major sixth, turning it into a Dorian-flavored chord. This removes the characteristic minor-key "sadness" and replaces it with a brighter, more jazz-influenced sound. Musicians should experiment with the placement of the iv chord, as it functions best when it precedes the V chord, creating a classic ii-V-i or iv-V-i motion that anchors the entire harmonic structure.

How does the relative major relationship influence chord choice and modulation?

Every minor key shares the exact same 7 notes as its relative major, located 3 semitones higher. This relationship allows composers to pivot freely between the two keys, using common chords like the III or VI to modulate without sounding abrupt or disjointed.

What are the common cadential patterns found in minor key music?

Cadential patterns in minor keys rely on the interaction between the dominant and tonic to provide a sense of finality.

• Authentic cadence follows the V-i progression, which is the most definitive way to end a phrase in a minor key.
• Plagal cadence uses the iv-i progression, often called the "amen" cadence, providing a softer, more reflective conclusion.
• Deceptive cadence moves from V to VI, delaying the resolution and creating a sense of surprise or continuation.
• Half cadence ends on the V chord, leaving the listener in a state of suspended tension.

How does the use of modal mixture expand the harmonic possibilities of a minor key?

Modal mixture introduces chords from the parallel major scale to expand the harmonic palette of a minor key.

Using these major-mode chords allows for unexpected shifts in mood, particularly when the major I chord replaces the minor i at the end of a piece. Apply these substitutions sparingly to maintain the core character of the minor key.