Cadences in Classical Harmony

A cadence in music is a melodic or harmonic formula that gives a sense of temporary or permanent conclusion at the end of a phrase, a section, or a composition. It serves the important musical functions of establishing tonality and marking various levels of formal structure.

Cadences in traditional harmonic practice fall into these categories: perfect, imperfect, deceptive, and masculine/feminine.

Perfect Cadences
A perfect (final, full) cadence is one generally regarded as satisfactory for the close of a composition. The final chord must be the tonic triad (I, built on the first degree of the scale) and must have the tonic note in the bass and the soprano. The penultimate chord may be either the dominant (V, built on the fifth degree of the scale) or the subdominant (IV, built on the fourth degree of the scale) in root position.

The progression V-I is an authentic cadence. If both chords are in root position and if the tonic is in the soprano of I, the cadence is called a perfect authentic cadence.

The progression IV-I is a plagal cadence. If both chords are in root position and if the tonic is in the soprano of I, the cadence is called a perfect plagal cadence. It is also known as an Amen cadence because it is often used to sing "Amen" at the end of Protestant hymns.

The extended perfect authentic formula IV-V-I or IV-I (second inversion)-V-I is sometimes referred to as a mixed cadence because the IV and the V are used together.

Imperfect Cadences
An imperfect cadence comes in three types.

(1) An authentic (V-I) or plagal (IV-I) cadence with the third or the fifth (instead of the tonic) in the soprano of I. This type is an imperfect authentic cadence or an imperfect plagal cadence.

(2) An authentic or plagal cadence with the penultimate chord (V or IV) in inversion (that is, with a note other than the root in the bass). Common examples include V in first inversion and II in first inversion as a substitute for IV. This type, too, is an imperfect authentic cadence or an imperfect plagal cadence.

Another name for this type is inverted cadence or medial cadence, as opposed to the root-position type, or radical cadence (Latin radix, "root").

(3) A cadence that ends not on I but on V or (sometimes) IV. This type of cadence occurs so often at the end of the first half of a musical phrase that it is termed a half cadence (or half close), specifically an authentic half cadence (on V) or a plagal half cadence (on IV).

Frequently the V is preceded by its own dominant (V of V). This secondary dominant itself does not change the status of the cadence from a half cadence in the first key to a modulation in a new key. To establish such a modulation, the cadence must be preceded by other strong chords in the new key.

Deceptive Cadence
A deceptive cadence is an authentic or (sometimes) plagal cadence in which I is replaced by some other chord. The most common substitute is VI or, because it has the same bass note, IV in first inversion.

Another frequent replacement for I is the diminished seventh chord built on the raised sixth degree (submediant) of the scale. This chord has a strong tendency to resolve to V.

Yet another favored substitute for I is I itself in an altered form so as to become the dominant seventh of IV, to which it normally resolves.

The deceptive cadence often serves as a link between two overlapping phrases. Phrases overlap when the second one begins simultaneously with the end of the first, both utilizing the same chord but with different purposes.

The deceptive cadence is an effective technique for raising musical tension and interest near the end of a composition.

Masculine/ Feminine Cadences
A cadence in which the final chord occurs on a metrically accented beat is a masculine cadence.

A cadence in which the final chord occurs on a metrically unaccented beat is a feminine cadence.
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Randel, Don Michael, ed. The Harvard Dictionary of Music. 4th ed. Cambridge, Mass.: Belknap Press--Harvard University Press, 2003.

Sadie, Stanley, ed. The New Grove Dictionary of Music and Musicians. 2nd ed. London: Macmillan, 2001.