Major and minor triads (chords) can be extended by adding specific
notes to the chord. The following list shows how we can play"extended-
chords" in the key of C major. Try these new chords:

C E G A (C6)

D F A C (Dm7)

E G B D (Em7)

F A C E (F major 7)

G B D F (G7)

A C E G (Am7)

B D F Ab (B diminished 7)

Now go back and "plug" the new chords into any progressions that you
have practiced for a new sound! For example, the I / vi / ii / V
progression in the key of G MAJOR would become:
G Major 7 / b minor 7 / E minor 7 / D7
Much more colorful than the original progression, right?
FORMULAS FOR EXTENDED CHORDS

Major Seventh Chord: 1 3 5 7 (the 1st,3rd,5th and 7th notes in the
major scale--example: CMAJ.7=C E G B)

Minor Seventh Chord: 1 b3 5 b7 (flat the 3rd and 7th notes in the
scale-- example: Cm7=C Eb G Bb)

Dominant Seventh Chord: 1 3 5 b7

Diminished Seventh Chord: 1 b3 b5 bb7 (double flat the seventh note)

Try extending the chords in several different keys and then using them
to compose some "colorful" chord progressions. In order to be
effective in using these extended chords, you must learn and practice
them in all 12 keys. Of course, in order to do that, you need to learn
the key signatures and the major scales. In the very near future I
will be writing articles on these subjects....

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