Harmonic Cadences

Harmonic cadences are moments in music that feel like an ending or resting point. They generally occur at the end of musical phrases, typically in the last two chords of a phrase.

Authentic Cadence: V(7) – I, V(7) – i, viio6 – I, viio6 – i

An authentic cadence involves a dominant chord moving to a tonic. This is the most important cadence, and arguably presents the strongest sense of finality. There are two types of athentic cadences: Perfect Authentic Cadences, and Imperfect Authentic Cadences. In a perfect authentic cadence, the chords must be V(7) to I, the soprano voice must end on scale degree 1, and the bass voice must move from scale degree 5 to 1. If any of these don’t occur, we have an imperfect authentic cadence.

Half Cadence: I – V, ii – V, IV – V, vi – V, i – V, iio6 – V, iv – V, VI – V

The half cadence always ends on V, and can feel incomplete by itself.

Deceptive Cadence: V(7) – vi, V(7) – VI (in minor)

As the name implies, deceptive cadences are intended to misdirect the listener. Where you might expect tonic, instead the dominant resolves to the submediant. Just like in an authentic cadence, scale degree 7 must resolve to 8.

Plagal Cadence: IV – I, iv – i

Nicknamed the “Amen Cadence,” as it often heard after the authentic cadence of many hymns.

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