The Six-Four Chord
The same three notes as any triad, with the fifth in the bass, and suddenly the chord cannot sit still. Four centuries of harmony treat it as a chord that must move. Play the three inversions in a row and you can hear why without reading a single rule.
- 2nd inversion
- fifth in the bass
- always moves on
In which styles
- Classical
- Hymns
- Film music
- Musical theatre
In short
With the root in the bass, the notes above it line up with the natural overtones of that bass note and the chord sounds settled. Put the fifth in the bass and the interval of a fourth appears above it, which your ear hears as leaning rather than resting. The chord is perfectly consonant and still sounds unfinished, which is exactly the property that makes it useful.
Suspended, like a held breath. The six-four chord is the sound of something about to happen, which is why it sits under the dramatic pause before a cadence so often that the position has its own name.
Where it sits in the phrase
Almost always immediately before the dominant. The cadential six-four delays the V by a beat or a bar, and that delay is what makes the eventual arrival land. The other uses are passing, where the bass walks through it, and pedal, where the bass stays put underneath.
Where you run into this
- The bar before a big cadence, where the music seems to hesitate
- A bass line walking down through a chord on its way somewhere else
- The start of a concerto cadenza, held until the soloist takes over
The types side by side
Cadential, passing and pedal six-four chords sound different because their context is different, not because the chord is. The cadential one is stressed and resolves to the V. The passing one is unstressed and the bass moves through it by step. The pedal one sits over a held bass and decorates. Play the three and the rule becomes a sound you recognise rather than a category you apply.
Keep going
Everything in harmony
- Harmonic Function
- Diatonic Chords
- Cadences
- Voice Leading Rules
- The Six-Four Chord