Introduction to Chromatic Mediants

What is a Chromatic Mediant?

A chromatic mediant is a type of chord transformation in which the chord root moves by third, and the new chord shares exactly one common tone with the previous one. They come in 8 distinct varieties¹:

• M3M - motion from a major chord to another major chord by 3 half steps (or a minor third up). For example, C Major to E♭ Major.
• M4M - motion from a major chord to another major chord by 4 half steps (or a major third up). For example, C Major to E Major.
• M8M - motion from a major chord to another major chord by 8 half steps (or a major third downward). For example, C Major to A♭ Major.
• M9M - motion from a major chord to another major chord by 9 half steps (or a minor third upward). For example, C Major to A Major.
• m3m - motion from a minor chord to another minor chord by 3 half steps (or a minor third up). For example, A Minor to C Minor.
• m4m - motion from a minor chord to another minor chord by 4 half steps (or a major third up). For example, A Minor to C♯ Minor.
• m8m - motion from a minor chord to another minor chord by 8 half steps (or a major third downward). For example, A Minor to F Minor.
• m9m - motion from a minor chord to another minor chord by 9 half steps (or a minor third upward). For example, A Minor to F♯ Minor.

As you can see, chords related by a chromatic mediants are always of the same mode (major or minor) and are always either a major third or minor third apart, in either direction.

...And make it double!

A doubly chromatic mediant is similar to a normal chromatic mediant, except that the new chord shares no common tones with the original chord. There are only four varieties of doubly chromatic mediants:

• M3m - motion from a major chord to a minor chord by 3 half steps (or a minor third up). For example, C Major to E♭ Minor.
• M8m - motion from a major chord to a minor chord by 8 half steps (or a major third down). For example, C Major to A♭ Minor.
• m4M - motion from a minor chord to a major chord by 4 half steps (or a major third up). For example, A Minor to C♯/♭ Major.
• m9M - motion from a minor chord to a major chord by 9 half steps (or a minor third down). For example, A Minor to F♯/♭ Major.

Doubly chromatic mediants are always of different modes, and there are only half as many of them!

But what about the others?

The remaining types of mediants (M3m, M9m, m3M, and m8M) are the regular diatonic mediants. They're quite ordinary, as they occur naturally in the major and minor scales.

Where to Find Them

Composers have been writing chromatic mediants since before tonality was established!

• In Early Music, chromatic mediants could be found in some styles of vernacular song, such as madrigals.
• In Baroque and Classical Music, chromatic mediants occur infrequently when tonicizing another key. They might also appear when modulating to the relative major after a half cadence (usually between movements).
• From Romantic Music onward, composers began using chromatic mediants more freely for dramatic and coloristic effect.
• In Video Game Music, composers use chromatic mediants to serve a wide variety of functions.

Notes

¹This website uses the Triadic-Tonal Progression Classes (TTPCs) proposed by Scott Murphy in his article "Transformational Theory and the Analysis of Film Music" (2013).