7th Chords

• There are 5 qualities of seventh chords that are normally used: major-major, major-minor, minor-minor, diminished-minor, and diminished-diminished. 

• The seventh chord quality is determined by the quality of the bottom triad and the seventh which the chord contains.

7th Chord Inversions

The notation for labeling seventh chords indicates the intervals formed with the bass.

E.g. - a seventh chord in 1st inversion (6/3) displays the intervals of a sixth, a fifth, and a third above the bass. As with triads, the figures for seventh chords are often abbreviated. Below is a table I made displaying the figured-bass numbers of the inversions associated with seventh chords I also provide the short-handed version in the  column all the way to the right:

Position	Chord Member in the Bass	Intervallic Content	Figured Bass Short Hand
root position	root	7/5/3	7
first inversion	third	6/5/3	6/5
second inversion	fifth	6/4/3	4/3
third inversion	seventh	6/4/2	4/2   or   2

The first inversion can also be written as just 5/3.

                                                        Diatonic 7th Chords in Major and Minor Keys

/

                  Diatonic - any stepwise arrangement of the seven  (scale degrees) forming an octave without changing the set pattern of a key or mode.

In a major key (M) when we add the 7th to each of these chords, I and IV are major 7th and V is dominant 7th. ii, iii, and vi are minor (m) 7th, and viiØ is half-diminished (this is also called minor (m) 7 flat 5). 

VIDEO REFERENCES