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Exploring chromatic mediant relationships

1 This month, we’ll jump straight in and look at a harmonised major scale. This is made by taking a major scale – C major in this case, seven notes played on the white notes of the keyboard from C to B – and stacking up alternate notes from the scale to get a series of diatonic three-note chords or triads. This gives us C, Dm, Em, F, G, Am and Bdim. 2 As you’ll know if you’re a regular reader of the EasyGuide, we can label these chords with Roman numerals so that we can describe chord progressions without worrying what key we’re in. Upper case numerals denote major chords and lower case denotes minor or diminished chords, so we get I, ii, iii, IV, V, vi and vii, as shown above. 3 As well as the Roman numerals, the diatonic chords also have names that describe their position in the scale, and these are shown here. The ones that we’re most interested in are going to be the mediant – the iii chord (which, in the case of C major, is E minor – E-G-B) – and the submediant – the vi chord ( Am in this case – A-C-E). 4 Chromatic mediants, then, are a set of altered mediant and submediant chords related to the tonic chord by means of being a major or minor third interval above or below it. So you could have a major third up, a major third down, a minor third up or a minor third down. Interestingly, these are non-diatonic chords – they don’t belong to the key. 5 This table shows all the possible chromatic mediants for the key of C

major. The reason the use of these chord types works so well in movie scores is that, through repeated conditioning that dates from the romantic era, the sound of the chords, when strung together, conveys a particular vibe that matches whatever’s happening on screen at that point. 6 So two chords can be said to have a chromatic mediant relationship if they are both major or both minor and their roots are a third apart. A common example is between two major triads with roots separated by a descending major third interval – ie, four semitones down.

Ab Here’s C major moving down to major – the common tone they share is C.

bVI 7 This movement can be spelt I > in numerals, because C major is the I chord, while the major chord rooted on the flattened Ab 6th degree of the C major scale is major. If we switch to a more dramatic sound to show this, (Dune CM’s

076 Phase String Pad RL preset), you can hear why this change is perfect for conveying a sense of magic and wonder. 8 Let’s check out some different approaches to onscreen scenarios. To underscore a heroic scene, for example, we could stick with two major triads, but this time play them a descending minor third interval (three semitones) apart, a movement spelt I > VI. So if we started on C major ( C-E-G), C# the next chord would be A major ( A- - E). 9 You get a more villainous overtone by using minor chords, like these two minor triads separated by an interval of a descending major third. Starting on an A

minor chord ( A-C-E), we move everything down four semitones Ab- from A to F and play an F minor chord ( F- C). Our common tone is C and the numeral bvi. formula for this movement would be i > 10 For an alternative, equally menacing vibe, try separating two minor triads by an interval of a descending minor third. This means that from our A minor chord ( A-C-E), we’d move our F# chord down F# three semitones F#- from C#). A to to get an minor chord ( A- Our common tone now is

A, with the Roman numeral formula for this movement being i > vi. 11 Let’s put all this into context. Here’s a drum track and a simple bassline in the key of A minor. Using the i > vi formula from the previous step, I’ve added a spacey synth pad and an arpeggiated synth part that alternates between F# the i chord ( Am) and the vi chord ( m), but with the vi chord played an octave down, so it’s a minor third below the i chord. 12 Lastly, I’ve extended the progression by adding two more chromatic mediant movements. F# First, move down a major third from m to Dm, then up from

Dm to Bm. The overall effect is one of impending menace. Note: all the chords here are played in root position (root note at the bottom of the chord), but that’s not essential to get the same effect.