10.12Seventh chords inside a major key

Let's build seventh chords using only notes of C major.

Scale:

C D E F G A B

Take every other note, four notes at a time.

On C

C E G B

= Cmaj7

On D

D F A C

= Dm7

On E

E G B D

= Em7

On F

F A C E

= Fmaj7

On G

G B D F

= G7

On A

A C E G

= Am7

On B

B D F A

= Bm7♭5 / Bø7

So the pattern in every major key is:

maj7 – m7 – m7 – maj7 – 7 – m7 – m7♭5

Roman numerals:

Imaj7 – iim7 – iiim7 – IVmaj7 – V7 – vim7 – viiø7

This is very important.