Chords are key components to understanding how songs work, and are usually major or minor chords; however, other varieties add depth and character to a song’s progression.
All seventh chords are composed on top of a basic triad and their quality is determined by the interval relationship between their notes.
Major Seventh
Major seventh chords (commonly referred to as maj7s) are one of the most prevalent seventh chords found in both major and minor key progressions, often constructed using only notes one, three, five, and seven from their scale.
Seventh chords can also be composed with close spacing to form an interval triangle of three outer tones and an inner tonic note; this is how they’re written on sheet music or lead sheets.
Major seventh chords (maj7) can often be found in rock, country and blues music – as well as jazz pieces by Wayne Shorter such as his tune Fall. Though major seventh chords initially caused some dissonance among musicians, they’ve now become an essential element of modern music.
Minor Seventh
Minor seventh chords (m7) combine the elements of a standard minor triad with the addition of a flatted third interval for added richness, elegance, and less loneliness than standard minor triads.
You will often hear this chord type used in blues and jazz songs such as Long train running by the Doobie Brothers and Ain’t no sunshine by Bill Whithers, respectively. Additionally, this chord can often be found used by Wayne Shorter in tunes such as Footprints and Fall.
You might also hear this chord used in other genres like pop and rock music. When using these chords, be sure that your bass note can carry its weight as necessary to play effectively.
Minor Seven Flat Five
Minor seven flat five chords, also referred to as half-diminished seventh chords or leading tone diminished seventh chords (since they serve as dominants within major key progression), are composed by adding a major third to a diminished triad, creating an interval composed of diminished fifth (5) + major third (3) that is equal to minor seventh flat five (b5) chord.
It may appear to be an intricate chord, yet its construction is actually straightforward: simply lower a minor seventh by one half-step and take its fifth note by half step steps back, as written out as Cm7(b5) or m7b5.
Note how even though there’s only a one-note difference between this chord and its full diminished seventh counterpart, that one note makes an enormous impactful statement about identity, function and emotion. Voice-leading from minor seventh to F# creates the distinctive sound of this chord.
Dominant Seventh
The dominant seventh chord is an excellent way to begin learning blues music as it is simple and effective. Comprised of both major and minor tones, its effects can range from happy or sad depending on its usage.
One reason the diminished chord is so useful is because it allows you to build tension before transitioning to a tonic chord at the end of a section or cadence; that is also why popular songs often employ it!
Building a dominant seventh chord requires stacking either a major triad or minor seventh above its root note, creating dissonant sounds with strong feelings reminiscent of those heard in piano music by Claude Debussy and others. You could even lower fifth to create half-diminished sevenths; C7b5 sounds very similar to Cm7.