Previously, I talked about the basic three-note chord types, the triads. To review, there are four basic types that are commonly used. Here they are with their interval formulas:
| Major | Minor | Augmented | Diminished |
| root, major third, perfect fifth | root, minor third, perfect fifth | root, major third, augmented fifth | root, minor third, diminished fifth |
To each of these chord types, we can add more notes to create more complicated chords. There is no limit to what we can add, but the most common type of note to add is a seventh, either a minor seventh, major seventh, or diminished seventh. As you can imagine, when combined with the four chord types we have to start with, this leads to, like, a million different chords (ok, actually 12, but you get the idea). Fortunately, some are used more frequently than others, and some are almost never used, so I’ll present the most common ones first.
Dominant Seventh Chords
The first and most important type of seventh chord to learn is the dominant seventh chord. In fact, this type is so common that it is usually referred to simply as a seventh chord. It is a major chord with an added minor seventh note. The minor seventh interval is also sometimes referred to as a dominant seventh, so that’s where the name comes from.
Dominant seventh chord interval formula: root, major third, perfect fifth, minor seventh.
So, for example, the notes in a G dominant seventh chord, written simply as G7, are G, B, D, and F. Notice that all those notes come from the C major scale. And this is a pattern. The seventh chord formed starting with the fifth note in a major scale and taking every other note is a dominant seventh. So just remember, the fifth chord is a seventh. Easy, right? To increase confusion, this is often written as V7. Notice also that this chord contains the two notes on either side of the tonic: that B and that D straddle the C. Along with the natural tension that a minor seventh chord contains, this makes the dominant seventh great for leading into the tonic chord. Try playing a G7, then a C major a few times. You will clearly hear the tension and resolution. This is a powerful tool that is used a lot in song composition. In fact, the song Sweet Dream Baby, by Roy Orbison uses only two chords: F, and C7 (which is the V7 chord in the key of F).
Here are some common dominant seventh chords and the most common ways to play them. One thing to note is that the C7 shape that is most commonly played in the open position on guitar is not technically a complete seventh chord, since it doesn’t include the fifth note, the G. This would more properly be written as C7(no 5). It sounds close enough to a full C7 that most people don’t care, though. Click on any chord name to see more ways to play it at The Chorderator.
A7
Notes: A, C#, E, G
B7
Notes: B, D#, F#, A
C7
Notes: C, E, G, Bb
D7
Notes: D, F#, A, C
E7
Notes: E, G#, B, D
G7
Notes: G, B, D, F
Major Seventh Chords
A major seventh chord is a major chord with a major seventh note added.
Major seventh chord interval formula: root, major third, perfect fifth, major seventh.
A C major seventh chord, for example, is written as Cmaj7 or CM7 (with a capital M), and contains the notes C, E, G, B. In the major scale, the four-note chords formed off of the root note and the fourth note are major sevenths. So in the key of C, the C and the F. These are often written as Imaj7 and IVmaj7.
A major seventh chord builds less tension than a dominant seventh, and so is a good chord to end a song on, if you want to go for a jazzy but kind of relaxed feel. I consider it to have an almost island-y sound.
Here are some common major seventh chords and the most common ways to play them:
Amaj7
Notes: A, C#, E, G#
Cmaj7
Notes: C, E, G, B
Dmaj7
Notes: D, F#, B, C#
Emaj7
Notes: E, G#, B, D#
Fmaj7
Notes: F, A, C, E
Gmaj7
Notes: G, B, D, F#
Minor Seventh Chords
A minor seventh chord is a minor chord with the dominant seventh added
Minor seventh chord interval formula: root, minor third, perfect fifth, minor seventh.
A D minor seventh chord, for example, is written as Dm7, and contains the notes D, F, A, C. In the major scale, the four-note chords formed off of the second, third, and sixth notes are minor sevenths. So in the key of C, you have Dm7, Em7 and Am7. These are often written as iim7, iiim7, and vim7.
A minor seventh chord can be used any place the regular minor chord would normally be used if you want a slightly more complex sound. One nice thing about minor sevenths is they are very close to the relative major chord. For example, if you look at the shape of the Am7, you’ll notice it’s like a C major chord, but you just pick up your third finger and play the fifth string open. So if you have a song where you’re transitioning from a C to an Am, you can play an Am7 instead, and keep a sense of continuity. (Read about relative minors.)
Here are some common minor seventh chords and the most common ways to play them. Click on any chord name to see more ways to play it at The Chorderator.
Am7
Notes: A, C, E, G
Bm7
Notes: B, D, F#, A
Dm7
Notes: D, F, A, C
Em7
Notes: E, G, B, D
Minor Major Seventh Chords
Yes, it is really called “minor major seventh.” It’s a minor chord with an added major seventh note.
Minor seventh chord interval formula: root, minor third, perfect fifth, major seventh.
We’re starting to get into the lesser used chords, at least in popular music. The minor major seventh chords come about when we form four-note chords from the harmonic minor scale. Starting from the first and third notes, specifically. For example, taking every other note in the A harmonic minor scale, we get an AmMaj7, which contains the notes A, C, E, G#.
I actually really like the sound of these chords, though they may sound a bit “dated” in modern music. They’re like the chord you hear when the gritty private detective learns a startling new clue in a 1940s movie. They’re pretty easy to play, so give them a shot and see if you can work them into some songs. Again, they can be used in place of any minor chord, but probably should be used a little more sparingly than minor sevenths. Let’s see if we can create a rebirth of their popularity.
“Common” may be too strong a word, but here are some major minor seventh chords that are relatively easy to play (for such a little-used chord type, it has some surprisingly easy open shapes):
AmMaj7
Notes: A, C, E, G#
BmMaj7
Notes: B, D, F#, A#
CmMaj7
Notes: C, Eb, G, B
DmMaj7
Notes: D, F, A, C#
EmMaj7
Notes: E, G, B, D#
And so on, and so on…
That’s probably enough chord types for one lesson. If there is interest, in the future I will tackle diminished sevenths, half-diminished sevenths, augmented sevenths, and all kinds of happy extensions.
Reference
Here is how the C major scale harmonizes with four-note chords:
| Imaj77 | iim7 | iiim7 | IVmaj7 | V7 | vim7 | viidim7 |
| C major seventh | D minor seventh | E minor seventh | F major seventh | G dominant seventh | A minor seventh | B diminished seventh |
Here are the chord types covered in this lesson:
| Triad | Added seventh | Chord name | Example |
| major | minor 7th | dominant seventh | C7 |
| major 7th | major seventh | Cmaj7 | |
| minor | minor 7th | minor seventh | Cm7 |
| major 7th | minor major seventh | CmMaj7 |