Lesson 22: Cadences

A cadence is a resting of a musical phrase. Phrases may rest briefly, such as in the middle of a melody, or more permanently, such as at the end of a melody. Our task in this lesson will be to study these cadences, and to be able to identify and write them.

Take a look at this melody, which has been harmonized with some basic chords:

  

If you play the melody, you can hear that there is a brief pause in bar 4 (the first arrow), and a more permanent-sounding conclusion in bar 8 (the 2nd arrow). The pause in bar 4 is not the sort of pause that we would want to end the melody on; we can hear that it wants to continue. The end of the melody has a more "final" sound. Those two spots in the music are called cadences.

The two types of cadences demonstrated by the example above are the half cadence (the one in bar 4), and the authentic cadence (the one at the end). Let's look at authentic cadences first.

AUTHENTIC CADENCE

An authentic cadence requires two things:

1) The resting of a musical phrase, and
2) a chord progression of V-I.

The melody above ends on a V-I chord progression, and it also rests (after all, it IS the end of the melody!) So it is an authentic cadence. It is similar to a period in written languages. There are two types of authentic cadences:

PERFECT Authentic Cadence:
A Perfect Authentic Cadence (PAC) requires that the V-chord and the I-chord are both root-position chords, with the topmost voice (soprano) ending on the tonic note. Here are some PAC's:

  

Notice that the V-chords in the minor keys have been altered to be major. Notice also that the soprano voice moves to finish on the tonic, and the bass voice moves either up a 4th, or down a 5th. That's because PACs must feature root position chords- NO INVERSIONS ALLOWED!

IMPERFECT Authentic Cadence:
An Imperfect Authentic Cadence (IAC) is a V-I progression, but allows for inversions, or permits the soprano voice to finish on a note other than the tonic. Here are some IACs. Try to figure out what makes them IAC, and not PAC:

  

In the F-major cadence, the fact that the first chord is an inversion (V6) makes it IAC. In the A-major cadence, the soprano ends on the mediant, not the tonic. In the Bb-major cadence, the V-chord is an inversion. In the last example, the soprano voice ends on the 5th of the chord, not the tonic.

HALF CADENCE

A half cadence (HC) requires two things:

1) The resting of a musical phrase, and
2) A chord progression that ends on a V-chord.

A half cadence is similar to a comma or semicolon in written languages. In the melody at the beginning of this lesson the half cadence occurs in bar 4. Play it again and notice that, although it rests, it fneeds to go on; it needs something more.

Here's a little ditty that features a half cadence in the middle and a perfect authentic cadence at the end:

  

Much of the time, a half cadence features the progression I-V, but it can be "anything" - V. Here are some half cadences:

  

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PLAGAL CADENCE

A plagal cadence (PC) is a progression that ends IV-I. It is often referred to as the "Amen" cadence, because it sounds like the "amen" that is sung at the end of many hymns. Here is a progression that features a plagal cadence at the end:

  

NOTE: Here is an interesting point you may want to ponder. In the example above, the progression V-I that you can see at the end of bar 1 into bar 2 can be thought of as the actual cadence, and the IV-I at the end as merely a "tag", or phrase extension, intended only to stretch out the ending a little longer. What do you think?

Here are some plagal cadences:

  

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SUMMARY

Here is a table with the various cadences:

Occasionally, a V-chord will cadence on something other than a I-chord. In such cases, the resulting cadence is known as a deceptive, or interrupted cadence. Most deceptive cadences follow the progression V-vi, since vi works as a relatively good substitution for I, and one can hear the "resting" of the phrase.