In minor keys, there is more to understand about the v chord.
Minor keys revolve around the natural minor scale. The v chord, when derived from the notes of the natural minor scale, falls as a minor triad or minor 7th chord. For example, in the key of A Minor the chord built on the fifth of the scale is an Em (E G B) or Em7 (E G B D). The notes in these chords all come from the A natural minor scale. In other words, they are diatonic.
In minor keys, however, there is a frequent harmonic “adjustment” made where the minor v chord of the natural minor scale is changed into a major triad or dominant 7th chord. The v chord becomes a V chord.
Let's look at what happens in this special situation. First, we will review how V chords work in major keys. Then, I will explain how the same sound is often applied in minor keys.
The Strong V Chord of Major Keys
Music's strongest harmonic movement is found in major keys where the V chord moves to the I chord. The tension of the dominant V chord resolves to the tonic I chord. In music theory this V-I progression is known as an authentic cadence or full cadence. A cadence is a harmonic or melodic structure at the end of a phrase or section of music.
What is it that creates tension in the V chord which pleasingly resolves to the I chord?
The satisfying resolution comes from two important notes inside of the V and I chords which are a half-step apart and smoothly connect from one to the next. These two important notes are called the leading tone and the tonic. The “leading tone” is another name for the seventh of the scale. “Tonic” is another name for the first note of the scale.
In every major key, the leading tone—the seventh note—is always a half-step below the tonic, or first note, of the key. For example, in the key of C major (C, D, E, F, G, A, B, C) the leading tone is B and the tonic is C. B is a half-step below C.
The leading tone is so named because it leads a listener's ear to the tonic. If you play up the notes of a major scale and pause on the leading tone, you will notice the tension of the leading tone wanting to resolve up a half-step to the tonic. Listen to this example where I play the major scale pausing on the leading tone:
The strength of the V-I chord progression comes from the same leading tone-to-tonic sound existing inside the two chords. The leading tone is heard inside the V chord and connects to the tonic heard inside the I chord. The third of the V chord is the leading tone of the key; the root of the I chord is the tonic of the key.
Let's look at this in the key of C (C D E F G A B). In the key of C the V chord is a G major triad spelled G-B-D. Notice the third of the G chord is B, the leading tone in the key of C.
The I chord is a C major triad spelled C-E-G. The note C is the root of the I chord and the tonic of the key. So, the B in the V chord smoothly resolves to the C in the I chord.
Listen to my I-V-I example to hear what this sounds like:
The same relationship happens in all major keys when you go from the V chord to the I chord. This half-step connection is the heart of the authentic (V-I) cadence.
Adding a Seventh to the V Chord
An even stronger relationship is created when you use the seventh chord built on the V of the major key. The seventh chord built on the V in a major key is a dominant 7th chord. Remember, the dominant 7th chord structure is root, 3, 5, flat 7. This dominant 7th chord creates a lot of tension due to the dissonant interval between the 3rd and 7th of the chord. For example, on a G7 chord (G B D F) the B and F form the dissonant tritone interval. It is called a “tritone” because the notes are 3 whole-steps apart.
When we play the V chord as a dominant 7th chord (often written V7) in the V7-I chord progression, one more smooth half-step connection occurs between the notes of the two chords. The 7th of the V chord descends a half-step to the third of the I chord.
For example, in the key of C the V7 chord would be G7 (G B D F). The seventh, F, descends a half-step to the E of the C chord (C E G). So, in this V7-I progression there is a tense tritone interval (3rd & 7th) in the V7 chord, and those two tense notes each resolve chromatically to the root and third of the tonic chord. This makes for a powerful chord progression.
Again, listen to the I-V-I progression with the 7th added to the V chord:
Why am I going on and on about a major scale progression when this block of lessons is focused on minor harmony? Because the harmony of the natural minor scale is missing this powerful sound.
The Weak v Chord of Minor Keys
In minor keys, the v chord happens to be minor, and the minor v chord to minor i chord doesn't produce the same kind of tension that a major triad or dominant V chord produces.
Why? It's because the third of the minor v chord falls a whole-step below the tonic.
In a natural minor scale the 7th is a whole-step below the tonic of the scale.
For example, in the key of A minor (A, B, C, D, E, F, G), G is a whole-step below A.
The minor v chord in the key of A minor is Em spelled E-G-B. v to i in a minor key has a weaker sound of G moving to A (a whole-step) where G♯ to A (a half-step) would be stronger.
Because of this weakness in minor keys, composers and songwriters often change the minor v chord to a major triad or dominant 7th chord to produce a stronger resolution of V to i.
When we change the minor v to a major or dominant V we raise its third. For example, in the key of A minor, the v chord derived from the notes of the key is Em (the notes E, G, and B). If we change this minor v chord to major we get the chord E (E, G♯, and B). Now a major V chord moving to a minor i chord has the strong leading tone (G♯) moving up a half-step to the tonic (A).
So, in minor keys, a popular chord progression is V-i instead of the weaker v-i. Let me play you an example:
When Do I Use a Minor v Chord vs. a Major V Chord?
Most of the time this decision is made by the composer of the song. It depends on the sound they wanted. If you're just playing a minor key song, you probably don't want to change the v to V or vice versa unless you're sure it's the right sound for the song. If you are writing the song or have some input, experiment with both sounds. There are a lot of possibilities.
This v to V alteration doesn't happen all of the time in minor key songs, but it happens quite often. It was very popular to do in Classical music. It happens in jazz most of the time. It occurs a lot in minor key Latin music. And, it occurs often, but less frequently, in rock, pop, R&B, country and other styles. Now that you know, you'll start to hear this sound everywhere.
Modify Your V Chord Shape
Now that you know your minor key v chord might sometimes be a V chord, you need to learn a new shape for it in our set of minor key chords.
How do you change minor to major? You raise the third. All you are doing here is raising the third of the minor v chord by a half-step. Notice the third of your major triad/dominant 7th chord is now a half-step below the tonic of the key. That third of the V chord is the leading tone of the key.
Since this is such a powerful sound, I'll give you another "upside-down" shape which goes lower. Again, see the 3rd is located a half-step below the first note of the key?
Finally, for extra credit, you can combine those two shapes into one very useful shape:
Is It Still the Same Minor Scale?
A question you might have is, if we are changing notes in the natural minor scale, is it still the same scale? Raising the 7th note of the natural minor scale forms a new minor scale which we will discuss next—the harmonic minor scale.