Reharmonize Hallelujah on Piano: Secondary Dominants and Tritone Subs (Part 3)

To reharmonize Hallelujah in C major, precede chords with their own dominant seventh (such as E7 before Am), expand those into 2-5-1 fills (Gm7-C7-F, Bm7b5-E7-Am), swap chords for common-tone relatives (Am7 or Em7 for C, Dm7 for F), replace G7 with its tritone substitute Db7, and lead into minor chords with a diminished seventh like G#dim7.

Video lesson by Jason Zac · Intermediate · 27 min

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What this lesson teaches

This is Part 3 of Jason Zac's reharmonization series on Leonard Cohen's Hallelujah, played in C major with the basic chords C, Am, F, G and the composer's own E7. It is for pianists who already know triads and seventh chords and want to take a familiar song outside the scale while still following classical and jazz theory. Jason deliberately applies each idea to almost every chord as an exercise; in a real cover you choose only the moments you like.

1. Secondary dominants

A secondary dominant is the chord a perfect fifth above your target chord, played as a major or, more strongly, a dominant seventh chord, resolving to that target. The circle of fifths, moving counterclockwise, shows every resolution: C7 to F, F7 to Bb, Bb7 to Eb, Eb7 to Ab, and so on round the circle back to G and C.

• E7 before Am: on the opening line, slip an E7 between C and Am, because E is the V of A.
• Protect the melody. Where the vocal note is G, play E7#9, since G against E works as the sharp nine. E7b9 is another colour.
• C7 before F and D7 before G work the same way.
• G going to C needs nothing, because G is already the V of C.

Hallelujah already contains one secondary dominant: the E7 going to Am on the word composing.

2. Two-five-one fills

Instead of just V to I, add the ii chord of the target, still moving in fourths round the circle. Use these fills where a chord lasts longer.

• Target F: Gm7 to C7 to F. The ii is minor, the V dominant, the I major. A dominant ii also works but sounds less colourful.
• Target a minor chord such as Am: use a half-diminished ii, Bm7b5 to E7 to Am. This draws on the A harmonic minor scale and gives a stronger minor mood.
• In the home key you can use Dm to G to C, or squeeze in a gospel-style chain of Am, D, G, C at the end of a phrase, which Jason compares to Norah Jones.

3. Common-tone chord substitution

Replace a chord with another chord from the scale that shares at least two of its notes.

• C (C E G) can become Am (A C E) or Em (E G B). Add sevenths for a washier sound: Am7 (A C E G) holds the whole C triad, so only the bass changes the mood.
• Am can become C.
• Use relative minors for the major chords: F becomes Dm or Dm7, G becomes Em. You can extend these with sevenths or ninths.

4. Tritone substitution

A dominant seventh chord (1, 3, 5, b7) can be replaced by the dominant seventh a tritone away. A tritone is a perfect fifth minus a semitone, or a perfect fourth plus a semitone. So G7 becomes Db7 (or C#7) on the line about not caring for music.

The plain Db7 clashes with the melody note G. Jason fixes this by flattening the fifth: Db7b5, with G in place of Ab, so the chord contains the melody note.

5. Diminished seventh before a minor chord

A diminished seventh chord is a stack of minor thirds. Before any Am, play G#dim7 (G# B D F). It acts almost like G7b9 without the G, a dominant pulling to the tonic, and you may add the G in the bass. Because of its symmetry, G#dim7 contains the same notes as Bdim7, Ddim7 and Fdim7.

How to practise

1. Play the plain progression first, then add one technique at a time.
2. Sing or play the melody over each new chord and alter chord tones (sharp nine, flat five) where they clash.
3. Save the bolder changes for later verses, keeping the opening simple.
4. Pick what suits your cover: change it without annihilating the song.

Questions about this lesson

What is a secondary dominant in Hallelujah?

It is a dominant seventh chord built a perfect fifth above the chord it resolves to. In C major, E7 resolving to Am is the secondary dominant the song already uses, and you can add others such as C7 before F and D7 before G.

What 2-5-1 should I use before a minor chord?

Use a half-diminished ii chord, then the dominant, then the minor chord. For Am that is Bm7b5, E7, Am, which comes from the A harmonic minor scale.

What is the tritone substitute for G7?

Db7 (also spelled C#7), because Db is a tritone from G. In Hallelujah, flattening its fifth to G makes it fit the melody better.

Which diminished chord works before A minor?

G#dim7 (G# B D F) leads well into Am, sounding like G7b9 without the G. It has the same notes as Bdim7, Ddim7 and Fdim7.

Practise it

• The Dominant SeventhStudy dominant-seventh harmony through musical examples.
• Master KeyExplore diminished-seventh harmony, its resolutions and sixth-diminished sounds.
• Piano classes at Nathaniel School of MusicLive online or in Bangalore, with a teacher.
• All free music apps40 practice tools for harmony, rhythm, ear training and more.

Related lessons

• Passing Chords Made Easy: Transform Your Piano Progressions Step by StepA passing chord places a chromatic bass note a semitone below a target diatonic chord, and in G major you can build it three ways: a major slash chord with its third in the bass (such as D/F# to G), a secondary dominant seventh (such as E7 to A minor), or a secondary diminished seventh (such as G#dim7 to A minor).
• 5 Ways to Make a Basic Chord Progression Sound BeautifulYou can make a basic two-chord progression like Bb major to D major sound richer by adding passing chords in between: relative minors, plagal (IV) chords, authentic (V) chords, secondary dominants, and ii-V-I approaches to the next chord, all found easily with the Circle of Fifths.
• Play and Sing Hallelujah on Piano and Reharmonize It (Part 1)To reharmonize Hallelujah on piano, start with its simple C major chords (C, Am, F, G, E7) and then colour them with add and sus chords, seventh and ninth extensions built by stacking a triad a fifth above the bass, and passing slash chords such as G/B, C/E and D/F# placed between the original chords.
• How to Make Piano Chords Sound Better: 8 Embellishment Techniques (Part 2)To make basic major and minor piano chords sound richer, change the time feel with a triplet at the end of the bar, weave diatonic thirds through the chord, add secondary dominants before target chords, and colour chords with extensions such as sevenths and ninths.