Making a Practical Plan for Minor Key Harmony

What are the primary differences between natural, harmonic, and melodic minor scales in a harmonic context?

The differences center on how the sixth and seventh degrees interact with the tonic. The natural minor scale provides a flat seventh, which lacks the pull needed for a strong resolution, while the harmonic minor raises the seventh to create a major dominant chord. The melodic minor further raises the sixth degree to avoid the awkward augmented second interval between the flat sixth and raised seventh. For instance, in A minor, the harmonic version uses a G# to define the E major chord, whereas the melodic version uses F# and G# to smooth out the ascent to A.

A nuance exists in modal interchange, where composers often borrow the flat sixth from the natural minor even when using the harmonic minor's raised seventh. This creates a distinct, melancholic color often found in film scores that avoids the overly classical sound of a pure melodic minor scale.

How do you determine the appropriate chord qualities for each scale degree in a minor key?

You determine chord qualities by stacking thirds on each scale degree using the harmonic minor scale as your primary template.

1. Build a tonic minor triad on the first degree, typically using a root, minor third, and perfect fifth.
2. Construct a diminished triad on the second degree, which serves as a common point of instability.
3. Form a major chord on the third degree to provide a bright contrast to the tonic.
4. Create a minor chord on the fourth degree, often used to lead into the dominant.
5. Build a major dominant chord on the fifth degree by sharpening the seventh scale degree.
6. Use major chords on the sixth and seventh degrees to complete the harmonic set.

What is the function of the leading tone in minor key cadences and how is it achieved?

The leading tone acts as a gravitational pull toward the tonic, narrowing the distance to a single semitone. By raising the seventh scale degree, you create a major V chord that demands resolution, which occurs in approximately 90% of standard minor key cadences to firmly establish the tonal center.

How does the use of the minor dominant chord (v) compare to the major dominant (V) in common practice harmony?

The major dominant (V) provides a definitive resolution to the tonic, while the minor dominant (v) functions more like a modal passing chord.

Use the major V7 chord to conclude phrases or sections, reserving the minor v chord for internal movements where you want to avoid a sense of arrival.

What are the most effective ways to utilize the subdominant minor (iv) chord to create emotional depth?

The minor subdominant (iv) introduces a flat sixth degree that creates a poignant, descending chromatic line toward the tonic. Placing this chord immediately before the V or i creates a classic "plagal" feel, often lowering the perceived energy level by 10 to 20 percent compared to a dominant-heavy progression.

How do you construct a functional progression that effectively establishes a minor tonic?

Start by establishing the tonic with a i-iv-V-i progression, ensuring the V chord is major to lock in the key. This sequence clearly outlines the tonal center while providing enough movement to keep the listener engaged. Many people assume that you must use every note of the minor scale in every measure, but you should actually prioritize the chord tones of the V-i relationship to ground the harmony. Focusing on these pillars prevents the progression from sounding aimless or overly chromatic, which often happens when composers try to incorporate too many scale variations simultaneously.

What role does voice leading play in resolving dissonant intervals within minor key progressions?

Voice leading makes sure that dissonant intervals resolve by moving to the nearest stable chord tones through smooth, stepwise motion.

• Major seconds should move by step to resolve the tension inherent in the harmonic minor's augmented second.
• Tritones require specific resolution where the leading tone moves up a half-step and the fourth degree moves down a half-step.
• Seventh chords demand that the seventh of the chord resolves downward by step to the third of the tonic.
• Leading tones must always ascend to the tonic to satisfy the ear's expectation for completion.

How can secondary dominants be applied to minor keys without disrupting the established tonal center?

Secondary dominants in minor keys function by temporarily tonicizing a non-tonic chord, usually the iv or the III. To apply these, you identify the target chord and build a major dominant chord a perfect fifth above it. For example, in A minor, you can precede the D minor (iv) chord with an A major chord, which acts as the V of iv. This creates a brief sense of arrival at the subdominant without permanently shifting the tonal center away from the home key.

A common nuance involves the use of secondary diminished chords instead of major dominants. These provide a more subtle, chromatic transition between chords. The primary risk is overusing these secondary functions, which can cause the listener to lose track of the original tonic if the secondary dominants occur too frequently or for too long.