7th chords are chords that have 4 notes. A root, 3rd, 5th, and 7th. 7th chords diversify the tonality in chord progressions and music, especially when compared to standard triads.
7th chords are first seen in baroque and classical music, but they are much more commonly used in modern day. 7th chords are so closely associated with jazz music, that many music listeners hear 7th chords and automatically think – “Jazz!”
7th chords are expressive. If major and minor are sad and happy, then 7th chords are dreamy, ethereal, tense, and melancholic. Today we are going to show you how to play these lush chords, and open up your musical mind for sound expression. Let’s get to it, shall we?
What Are 7th Chords
7th chords introduce an additional chord tone above the standard triad. They have 4 notes instead of 3. The tones are root, 3rd, 5th, and 7th. It is the different qualities of these simple intervals that gives us 5 different 7th chords to use in any given context.
These 5 types of 7th chords are: Major 7th, Dominant 7th, minor 7th, half diminished, and diminished.
Types Of 7th Chords
Major 7th Chords
Major 7th chords are dreamy.
The simple formula for a major 7th chord is major triad + major 7th. When analyzing 7th chords, it is important to consider the relationship between the 7th and the root. You will notice that the interval of a major 7th is always one half step below the root note.
In a major key, the I and IV chords are major 7th chords. In a minor key, the III and the VI are major 7th chords.
Major chords can be written as Maj7, M7, or Δ7.
How To Play Each Major7 Chord
Dominant 7th Chords
Dominant chords (also called major-minor chords) are full of tension and instability. These chords are not meant to end a piece, but to be the dramatic climax right before resolution to the final tonic chord. Dominant 7th chords only occur on the V7 or a major or minor key.
Dominant 7 chords are built by adding a major triad and a minor 7th. The minor 7th always lies one whole step below the root note.
In both major and minor keys, the V7 is a dominant 7 chord.
The symbol for dominant chords is a “7” such as “C7”
Minor 7th Chords
Minor 7th chords are melancholic. They give a sense of longing and sorrow.
We build minor 7th chords by adding a minor triad and a minor 7th.
In a major key, the ii, iii, and vi chords are minor 7ths. In a minor key, the i, and vi chords are minor 7ths.
The chord symbol for minor 7 is simply “min7” or “-7”
Half Diminished 7th Chords
Half diminished (aka m7b5) chords are tense and unstable. Their sound is bittersweet. Half diminished chords are usually played before the dominant chord.
Half diminished chords are built by stacking a diminished triad and a minor 7th.
In a major key, the viiø7 is half diminished. In a minor key the iiø7 is half diminished.
The symbol for half diminished is “m7b5”
Diminished 7th Chords
Diminished 7th chords (sometimes called “fully diminished 7 chords”) are dramatic and suspenseful.
Fully diminished 7th chords are built with a diminished triad and a diminished 7th.
The only naturally occurring fully diminished 7th chord is the vii°7 in minor
The symbol for diminished is the same as the degree symbol. “°”
Easy 7th Chord Shapes
Now that we have gone over the theoretical makeup of these 5 unique chords, it’s time to learn how to apply them to the guitar. Here are 5 shapes to try and learn how each 7th chord sounds and compares to one another.
Diatonic 7th Chords
You may be wondering how you know when to play a minor chord vs a major chord. Or when to play a half diminished or a diminished. There is a system for that called diatonic chords. When we follow the key signature of a scale, each chord naturally takes on a particular quality. Here are the diatonic 7th chords in major and minor.
Major: IM7 ii7 iii7 IVM7 V7 vi7 vii viiø7
Minor: i7 iiø7 IIIM7 iv7 V7 VIM7 viio7
Oftentimes, minor keys conform to the harmonic minor scale, which raises the 7th scale degree. That is why the V chord is a V7 and not v.
Frequently Asked Questions
What are 7th chords on a guitar?
7 chords are chords that use the 7th of a scale. On the guitar, all 7th chords have shapes that can be remembered and played on any root note.
What is the rule of 7th chords?
The rule of 7th chords is that they are built on a root, 3rd, 5th, and 7th. Sometimes the 5th is left out, because it is implied.
What are the 5 qualities of 7th chords?
The 5 qualities of 7th chords are major 7, dominant 7, minor 7, half diminished 7, and diminished 7.
At first, the idea of 5 different types of 7th chords is daunting, especially because they have so many similarities, but once you can learn to hear the difference it all begins to make sense!
7th chords are chords with 4 notes. The notes are a root, 3rd, 5th, and 7th. There are 5 different types of 7th chords: Major 7th chords, dominant 7th chords, minor 7th chords, half diminished 7th chords, and fully diminished 7th chords.
Hope you learned a lot from this introduction to 7th chords on the guitar!