Diatonic Seventh Chords
(Music Theory Lesson

print


In addition to diatonic triads, every major and minor scale has seven diatonic seventh chords.

Let's examine the diatonic seventh chords of the C major scale.




First, construct the scale.




Next, stack three generic thirds on top of each note.




Finally, analyze the resulting seventh chords.




The first chord is C--E--G--B, a major triad and a major seventh. Therefore, it is a major seventh chord.




The second chord is D--F--A--C, a minor triad and a minor seventh. Therefore, it is a minor seventh chord.




The third chord is E--G--B--D, a minor triad and a minor seventh. Therefore, it is also a minor seventh chord.




The fourth chord is F--A--C--E, a major triad and a major seventh. Therefore, it is a major seventh chord.




The fifth chord is G--B--D--F, a major triad and a minor seventh. Therefore, it is a dominant seventh chord.




The sixth chord is A--C--E--G, a minor triad and a minor seventh. Therefore, it is a minor seventh chord.




The seventh chord is B--D--F--A, a diminished triad and a minor seventh. Therefore, it is a half-diminished seventh chord.




The eighth chord is a repetition of the first (C--E--G--B), making it a major seventh chord.The first seventh chord of a major scale will always be a major seventh, the second and third seventh chords will always be minor sevenths, etc.




Next, we will uncover the diatonic seventh chords of the C Natural Minor scale.




The first chord is C--Eb--G--Bb, a minor triad and a minor seventh. Therefore, it is a minor seventh chord.




The second chord is D--F--Ab--C, a diminished triad and a minor seventh. Therefore, it is a half-diminished seventh chord.




The third chord is Eb--G--Bb--D, a major triad and a major seventh. Therefore, it is a major seventh chord.




The fourth chord is F--Ab--C--Eb, a minor triad and a minor seventh. Therefore, it is minor seventh chord.




The fifth chord is G--Bb--D--F, a minor triad and a minor seventh. Therefore, it is also a minor seventh chord.




The sixth chord is Ab--C--Eb--G, a major triad and a major seventh. Therefore, it is a major seventh chord.




The seventh chord is Bb--D--F--Ab, a major triad and a minor seventh. Therefore, it is a dominant seventh chord.




The eighth chord is a repetition of the first (C--Eb--G--Bb), making it a minor seventh chord.




Next, we will discuss the diatonic seventh chords of harmonic minor.




To convert natural minor to harmonic minor, the seventh tone is raised a half step. Therefore, each Bb (the seventh tone of C minor) is raised to a B.




Each chord which contained a Bb needs to be reanalyzed. The first chord is now C--Eb--G--B, a minor triad and an major seventh. Therefore, it is minor-major seventh chord.




The third chord is now Eb--G--B--D, an augmented triad and an major seventh. Therefore, it is augmented-major seventh chord.




The fifth chord is now G--B--D--F, a major triad and a minor seventh. Therefore, it is a dominant seventh chord.




The seventh chord is now B--D--F--Ab, a diminished triad and a diminished seventh. Therefore, it is a fully-diminished seventh chord.




The eighth chord is a repetition of the first (C--Eb--G--Bb), making it a minor-major seventh chord.




We will now discuss the analysis symbols for diatonic seventh chords.Recall the symbols for the harmonic minor diatonic triads.




We simply add a small seven to the top right corner of each roman numeral.




If the seventh chord is half diminished, a slash is placed through the circle.




Use this chart to reference the diatonic seventh chords in each scale.














Other Music Theory Articles








All music theory articles are copyright Ricci Adams, reproduced by kind permission. Except where otherwise noted, these theory lessons are licensed under a Creative Commons License.