23.2 · The Other Chords

6, m6 & add9

Adding a third on top makes a 7th chord, and 7ths add pull. These chords add a note without building a 7th: pure color, no extra tension. Think of them as sweeteners. The triad still does the work, the added note only colors it.

Three sweeteners on C

A 6th, a 6th on minor, and a 9th floating an octave up. Each one note away from a plain triad.

432CEGA9the old-Hollywood ending: doo-wop and swing tunes close here
342CE♭GA9minor, vintage: noir soundtracks, gypsy jazz
437CEGD14the shimmer: 90s acoustic guitar's favorite chord

Sweetener or 7th?

C6 and Cmaj7 differ by one note (A vs. B) but land differently: the 6th settles, the maj7 hovers. Three endings for the same phrase:

Add 9 vs. sus2: one keeps the third

Both feature the 2nd/9th, but add9 keeps its third (still major!) while sus2 gave its third away (neutral). Back to back:

Game · Which sweetener?

1 / 6

A C chord, plain or sweetened. Which one did you hear?

Listen first. Then answer.

Quiz

1 / 3

What separates a sweetener (6, add9) from a 7th chord?

Score 100% on every quiz and game to complete this lesson. A perfect run sticks: a later miss never undoes it.°7, ø7 & mMaj7 →