In our previous lesson we constructed 3-note Triad chords. The simplistic sound of a triad might suffice for some genres of music, but Jazz most definitely requires the more complex coloring of chords containing more than three different notes.
The minimum requirement to be considered as a Jazz Chord is a 4-note chord. When the fourth note is added three or four semitones above the top note of a triad, the triad becomes what is called a ‘seventh’ chord. The notes of chords constructed in this manner referred to as:
- the ROOT
- the THIRD
- the FIFTH
- the SEVENTH
Just so you can hear the difference between triads and ‘seventh’ chords, listen to me first play the triads in the key of C from our last lesson:
Now listen to these same chords played as ‘seventh’ chords with a fourth note added on top:
You construct these ‘seventh’ chords by simply adding one note on top of a triad. Take the C triad for example. We started with C as our root, then added notes by skipping white notes: play C, skip D, play E, skip F, play G. Repeating this we skip A and play B. This gives us a C Major Seven(th) chord.
Think about this C Major Seven chord:
- we know that the root of this chord is C.
- we know that the E note is two whole tones above the root.
- we know that the G note is seven semitones above the root.
- these intervals for the E and G notes DEFINE a ‘Major’ chord.
- by adding the B note we created a C Major SEVEN(TH) chord.
Up to this point we have considered INTERVALS as being the distance between two notes by counting semitone or whole tone steps between the two notes.
But now we want to consider a more convenient method for describing the relationship between each note of the chord and the root note. To do so, we introduce the terminology “second”, “third”, “fourth”, “fifth”, “sixth”, “seventh”, “octave”, “ninth”, “tenth”, “eleventh” and “thirteenth” (there is no “twelfth”).
Let’s demonstrate this using our new C Major Seventh chord in the key of C. Starting from the root note C, we name the white notes above C as follows:
- D is the “second”
- E is the “third”
- F is the “fourth”
- G is the “fifth”
- A is the “sixth”
- B is the “seventh” (thus the name C Major ‘seventh’)
- C is an “octave” above the C root
- D is the “ninth”
- E is the “tenth”
- F is the “eleventh”
- A is the “thirteenth”
You might have noticed the duplication above the octave note. The usefulness of this will become clear shortly.