Seventh chords can add vibrant color and dimension to your song arrangements, featuring twisty chord shapes made up of major and minor triads.
To create a seventh chord, combine the third, fifth, and seventh intervals from above the root of a triad. There are five types of seventh chords: major, minor, dominant, diminished and half-diminished.
Major Seventh
Once you’ve mastered beginner chords, seventh chords offer a powerful step up in complexity. Adding emotion and color to chord progressions by including dissonant notes often discordant to their harmonic structure. There are four primary categories of seventh chords: major, minor, dominant and half-diminished.
Major seventh chords combine a major triad and major interval above its root; for instance, C major is composed of C-E-G with F# being added above it to form Cmaj7 chords on charts. When seeing such chords written out it indicates the roots being at C and its seventh being F#.
Major seventh chords come in various forms, but one easy way to create it is by starting from a major triad and adding F#. Below are four drop 2 major seventh chord voicings on guitar neck – these feature third highest notes being dropped an octave lower to create each drop 2 chord shape; to play each one requires placing your finger on sixth string and playing.
Minor Seventh
This chord adds some melancholic notes to any progression and serves as an excellent way to add tension. It is one of five seventh chord qualities (maj7, min7, dom7, m7b5, and dim7) used by harmony as tools to communicate emotions through song.
CAGED chords allow us to easily create open minor seventh chords of various varieties using shapes that can be moved up and down the fretboard for easy playability. Below are four such shapes (named by root note) with their accompanying guitar neck diagrams.
Patsy Cline’s iconic song, “Crazy”, serves as an excellent demonstration of how minor seventh chords can add an achingly sorrowful quality to songs.
Dominant Seventh
The dominant seventh chord can add tension to songs. These chords combine a major triad with a flat seventh note above the root, producing a bluesy sound – you may recognize these types of chords from hits such as John Lee Hooker’s “Boom Boom” or Muddy Waters’s “Blues Before Sunrise”.
Dominant seventh chords (V7 or V-chords) are named so because they’re composed of chords built upon the fifth scale degree (or dominant) of a key. Their tritone composition contributes to their dissonant, harsh sound.
To play a dominant seventh chord on guitar, simply fret a D Major chord shape with your fourth finger on the G string at its third fret and move your fourth finger up or down the neck to create different movable dominant seventh voicings (for example: C dominant seventh is an exact mirror image of D major).
Half-Diminished Seventh
Half diminished 7th chords (also referred to as m7b5 chords) are minor 7th chords with their perfect 5th interval flattened by a semitone, creating less stable chords with some dissonance; hence their use in connecting chords rather than building music is often preferred.
As with an altered 5th chord, the same interval pattern used to build a major 7th chord applies here as well. The name of this chord comes from what intervals we stack atop each other: minor third plus major third equals half diminished seventh chord.
So to create an m7b5 chord you simply stack two intervals of a major 3rd on top of each other to form A, C and Eb notes. While normally you would avoid duplicating notes in a triad due to potential voice crossing issues, dim7 chords do not suffer this problem as their lower 5th already provides this feature.