Borrowed Chords
Identifying Borrowed Chords
The concept of borrowing a note from the parallel major or minor key is also referred to as mode mixture. In a minor key there are three pitches that are lowered a half-step from the same scale degree in a major key. These are the 3rd, 6th, and 7th. When one or two of these scale degrees are borrowed from the parallel minor into the major key, a new chord quality appears. When a m3, m6, or m7 is imported from a minor key into its parallel major, a borrowed chord is formed.
The most commonly borrowed pitch is the m6th. Using this pitch to replace the 3rd of a subdominant triad (IV) in a major key yields a subdominant minor chord (iv). In the key of C, a diatonic IV chord is spelled F-A-C. The minor iv chord, created by borrowing the m6th, is spelled F-A♭-C. This can add interest and unexpected color to the music.
In his Symphony in E Minor (From the New World), Dvorak wrote a passage full of borrowed chords. Listen to the transposed piano reduction below, and note the chromatic mediant relationships.
Example of Borrowed Chords and Mode Mixture
It is much less common to see a major scale degree borrowed into the parallel minor. However, a major 3rd borrowed for the tonic chord at the final cadence is frequently encountered. This is referred to as a Picardy third.
The following chart shows the function and quality of diatonic triads and 7th chords used in both major and minor keys. When one of the these chords is borrowed from the parallel minor or major key it creates mode mixture. One chord missing from the chart is the subtonic, built on the lowered 7th scale degree found in the descending melodic minor mode. The use of this scale degree produces the major VII triad and VII7, as well and a minor v chord.
Voice-Leading Borrowed Chords
Given that lowered scale degrees generally resolve downward in the direction of their inflection, the minor 3rd, 6th, and 7th usually resolve to the pitch a half-step below. Altered tones are rarely doubled in four-voice harmony, with the exception of the triad built on the lowered 6th scale degree (VI) in a major key.
Materials
Examples for Analysis
Analyze the tonal areas, chords, cadences, non-chord tones, and form of these compositions.
Frederic Chopin, Valse Brillante, Op. 34 (PDF)