Dominant Seventh Chord

Theoretical information

A dominant seventh chord, or major-minor seventh chord, is a chord composed of a root, major third, perfect fifth, and minor seventh. It can be also viewed as a major triad with an additional minor seventh. When using popular-music symbols, it is denoted by adding a superscript «7» after the letter designating the chord root. The dominant seventh is found almost as often as the dominant triad. In Roman numerals it is represented as V7.

Root Position V7 – root in bass;

Inversions Dominant Seventh Chord 

Seventh chords can be inverted by moving the lowest note up an octave. Root position is the same as a triad — the root is the lowest (bass) note.

First inversion: V6/5 – 3rd in bass;  
Second inversion: V4/3 – 5th in bass;  
Third inversion: V 4/2 — 7th in bass.  

Resolving Dominant Seventh Chord and Its Inversions
Resolving V7 in Root Position: The dominant seventh chord resolves to a major or minor chord whose root is a perfect fifth below its root. In the case of the G dominant seventh chord which is the chord of the fifth degree in the key of C major, the G dominant seventh chord resolves downward by a perfect fifth.  
Six-five chord D6/5 – I 3;  
Four-three chord D4/3 – I 5/3;  
Four-two chord D4/2 – I 6.  
In the harmonic minor, the inversions of D7 are solved similarly.

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