Seventh Chord Construction // Dominant Seventh Chords (3 of 5)
Run time: 4m 55s | Release Date: January 1st, 2021
Section 1 - "Introduction"
The Dominant seventh chord is a very important chord in traditional music theory. Playing a Dominant chord before the tonic creates a strong feeling of resolution for the listener. Adding an interval of a seventh to the root note of a Dominant chord only enhances the anticipation of the tonic. Don't worry. More information on chord functions will be made available in future videos.
Dominant seventh chords are ubiquitous in many contemporary genres of music including jazz, rock, and specifically the blues.
Section 2 - "Major Triad Plus Minor Seventh"
So far in this video series we have learned how the notes of a Major seventh chord consist of a Major triad with the addition of an interval of a Major seventh above the root note, while a minor seventh chord consists of the notes of a minor triad with the addition of an interval of a minor seventh above the root note.
A Dominant seventh chord is unique in that it consists of the notes of a Major triad but with the addition of an interval of a minor seventh above the root note. This combination of a Major triad and minor seventh interval is what gives the Dominant seventh chord its defining sound.
To get a better idea, let's put together a Dominant seventh chord above the root note C. The notes of a C Major triad are C, E and G, and an interval of a minor seventh above the note C is the note B-flat. By playing the notes of a C Major triad together with the note B-flat we will have constructed a C Dominant seventh chord.
In that same way, the notes of a G Major triad are G, B, and D, and an interval of a minor seventh above the note G is the note F. By adding F to the notes of a G Major triad we will have created a G Dominant seventh chord.
Section 3 - "Constructed From A Mixolydian Scale"
Because of the combination of Major triad and minor seventh interval, the notes of a Dominant seventh chord may not be taken from either a single Major or minor scale. Rather, the scale from which the notes of a Dominant seventh chord may be derived is the Mixolydian mode.
Now, the notes of Mixolydian are very similar to the notes of a Major scale with the exception of a very important flattened seventh scale degree. Here are the notes of D Mixolydian. If we play the first scale degree, D, together with the third scale degree, F-sharp, the fifth scale degree, A, and the seventh scale degree, C, we will be playing the notes of a D Dominant seventh chord.
For more information on modes, please watch our video covering this subject by clicking on the link in the description below.
Section 4 - "Interval Pattern"
Similar to Major and minor seventh chords, Dominant seventh chords may also be constructed by following a specific pattern of intervals above a given note: Major third, minor third, minor third.
Let's use this interval pattern to construct a Dominant seventh chord above the note F. An interval of a Major third above the note F is the note A, an interval of a minor third above the note A is the note C, and an interval of a minor third above C is the note E-flat. Here we can see that the notes of an F Dominant seventh chord are F, A, C, and E.
Use this pattern of intervals to construct a Dominant seventh chord above any given note.
Section 5 - "Wrap Up"
In the next video we are going to discuss how to construct a half diminished seventh chord, also known as minor seventh flat-five.
Throughout this video series we have learned how the two components which construct a seventh chord are a triad and an interval of a seventh above its root note. A half diminished seventh chord is called so because only the triad component is diminished, while the interval of a seventh is minor.
Now, the notes of a diminished triad are very similar to the notes of a minor triad with the exception of a flattened fifth. For example, if the notes of an A minor triad are A, C, and E, then the notes of a diminished triad would be A, C, and E-flat. By adding an interval of a minor seventh above the note A to the notes of an A diminished triad we would then be playing an A half diminished seventh chord.