In the previous lesson, we learned how to create 7th chords from a major harmonic field. All we need to do is to overlap another third to the existing triad, and it will result in a 4-note chord (or tetrad) as shown in the image below:
Notice that we are just using notes from the given major scale.
If you’re not comfortable with 7th chords, I recommend you to read the corresponding lesson about it. A 7th chord will add a ‘tension’ in the chord, which will be responsible for creating interesting chord progressions.
Today we will learn that by adding a 7th to the harmonic field, each scale degree will result in a specific chord type. To better understand that, let’s review the resulting triads from a C Major harmonic field:
So, each scale degree will create a specific chord type:
– Degrees I, IV, V and VIII will always result in a major triad.
– Degrees II, III, and VI will always result in a minor triad
– Degree VII will always result in a diminished triad.
When we adding a 7th in the harmonic field, we create more specific chord types, as seen below:
– Degrees I, IV and VIII will always result in a major 7th chord;
– Degrees II, III and VI will always result in a minor 7th chord;
– Degree V will always result in a dominant 7th chord;
– Degree VII will always result in a half-diminished 7th chord.
Let’s now build the harmonic field for G Major scale:
And for F Major scale:
Notice that, although the chords are different, their types are the same. Your homework for this week will be to build the harmonic fields for D Major and Bb Major scales (all with 7th chords).
Each chord type will have an important role in a song. That will be the subject of our next lesson.
Happy productions!
