Check for Understanding
Consider the following two progressions:
Which progression would you expect to sound more similar to the basic progression (shown below)?
V⁷, the only seventh chord with a dominant seventh quality, has a function that is quite specific. The extra dissonance that it has compared to the basic V chord serves to strengthen the already strong pull of V back to I. While a basic V chord can be found in the middle of a progression and doesn’t need to go back to I, the V⁷ wants to resolve its dissonance by returning there. V⁷ is thus usually found at the end of a progression as a strong cadence chord.
“Twist and Shout” by The Beatles is a good example of a song that uses the V⁷ as a strong cadence back to I.
There are exceptions to this rule, of course. When we discuss the role of deception in a later chapter, we’ll learn that songwriters sometimes use the strong pull of the V⁷ to set up an expectation of returning to I, only to fool us by going somewhere else. Also, though beyond the scope of this chapter, blues and jazz make extensive use of dominant seventh chords in many other contexts. Nevertheless, this tendency is strong. Below is a chart showing the likelihood of what the next chord to come after a iV⁷ will be, using data from Hooktheory's Theorytab library.
In over half the cases in which V⁷ shows up in songs in the Theorytab library, the next chord is a I chord. The other chords all occur less than 10% of the time.
You can explore other trends in the way chords are used with Hooktheory's free Trends tool.
Open TrendsHere are a few more examples of songs using a V⁷ as a strong cadence back to I:
The ii⁷, iii⁷, and vi⁷ chords all have a minor seventh quality. While the dominant seventh quality of the V⁷ created more tension and a strong pull back to I, minor seventh chords are more subdued in their function. Compared to their basic non-seventh counterparts, the minor seventh chords have what could be described as a more mellow, complex sound that gives a distinctive feel or style to a song.
This sound lends itself to certain genres better than others. For instance, if you want to write a simple folk song like “This Land Is Your Land” (above), you probably shouldn’t use a lot of minor seventh chords. The complexity of the minor seventh chord tends to give a sound that isn’t quite right for this genre (on the other hand, the dominant seventh V⁷ cadencing to iI is very popular in folk songs). However, if you want to write a sophisticated sounding pop ballad, you should have at it! Functionally, it’s usually appropriate to directly substitute a ii⁷ for a ii and a vi⁷ for a vi, etc. If you want your basic progression to sound more complex or sophisticated, try changing some of your minor chords to minor sevenths. Mariah Carey uses this technique in “Underneath The Stars”:
The most important thing to take away from this discussion about minor seventh chords is that making a minor chord a minor seventh chord doesn’t change its function very much. A iii⁷ chord acts very much like a regular iii chord, for example. To see that this is true, consider the following charts using data from our Theorytab library showing the likeliest chords to come after iii and iii⁷:
The figures above show a concept that we first learned about in Hooktheory I; the iii chord has a very strong tendency to go to IV or vi. We now see that this remains true of the iii⁷ as well. Take, for example, Frankie Valli’s hit, “Can’t Take My Eyes Off You”:
In this case, the vi chord that the iii⁷ goes to is actually a vi⁷, following the principle that minor seventh chords are generally substitutable for their basic non-seventh analogs.
You may have noticed that several of the songs above also used major seventh chords in their progressions. Let’s discuss how those work now.
Compared with minor seventh chords, major seventh chords stand out more. Minor seventh chords also stand out, of course, but they are a bit more understated. On the other hand, when a song uses a major seventh chord, you tend to notice.
Recall that the two basic chords that become major sevenths are the I chord and the IV chord. Making the I chord a I⁷ is an interesting choice because you’re changing the feel of the home base chord. Changing the quality of the home base chord can give your song a more mellow, jazzy feel, as in “Underneath The Stars” from the previous section.
“Clarity” by John Mayer is an example of a song that makes use of both the I⁷ and the IV⁷. The first version plays the chords as written by Mayer. The second version removes the sevenths so you can hear what the basic version sounds like.
While major sevenths tend to stand out more than minor sevenths, keep in mind there is still only a single note differentiating a basic chord from a seventh chord. This is true for all seventh chords, of course, and the degree to which a seventh chord changes the feel of a song depends a great deal on how much emphasis this extra note gets in the music. Listen to this section of “Fallin’ For You” by Colbie Caillat
In the actual recording of this song, Callait subtly changes one note to go from iI to I⁷. Then she uses a IV⁷ that could easily be mistaken for a basic IV unless you are listening carefully. The seventh chords are played lightly on an acoustic guitar so their effect is nuanced. Compare this to the dominant V⁷ chord in “Twist and Shout” by The Beatles:
The extra note that makes the V a V⁷ (scale degree 4) is literally shouted at you by the vocalist in the melody. How these more complex chords are perceived greatly depends on the instrumentation and skill of the person performing the music. A trained piano player, for example, can shape the sound that is produced by controlling the volume of individual keys to make certain tones stand out more than others.
“Suit & Tie” by Justin Timberlake mixes both major and minor sevenths to create a soulful R & B sound:
Notice how the dissonance added by the prominent use of scale degree 3 in the accompanying melody makes the ii⁷ stand out a bit more than it otherwise would. As with the previous examples, the melody and arrangement can play a large role in shaping how the harmony is felt.
“Gimme All Your Love” by Alabama Shakes is another soulful tune that uses both IV⁷ and I⁷:
Check for Understanding
Consider the following two progressions:
Which progression would you expect to sound more similar to the basic progression (shown below)?
In the next section we’ll look at how inversions of seventh chords can be used to further alter their functionality and spice up your music.
Next up: Inversions of Seventh Chords