My NYU aural skills students are working on chord identification. My last post talked about seventh chords; this post is about chords with more notes in them, or at least, different notes. My theory colleagues call them added-note chords. They are more commonly called jazz chords, though many of the examples I list below are not from jazz. You could also call them extended chords, or complicated chords, or fancy chords, or cool chords. It’s easy to get overwhelmed by all the numbers and symbols. My preferred way to organize all this information is to think of chords as vertically stacked scales. It is intimidating to try to learn to distinguish between C7, C9, C13, C7sus4, C9sus4 and C13sus4, but they are really just different combinations of the notes in C Mixolydian mode, and they all convey a similar “Mixolydian-ness”. But before we get to those, let’s start with extended chords you can make from regular old C major.
Major scale chords
Sus4 chords
To make a sus4 chord, you take a major triad and raise its third up a half step to the fourth. In classical music, the idea is that the third is being lifted up to the fourth temporarily, and that it will soon return back to its proper place. In rock and pop, that might also be the case, but sometimes the sus4 chord is itself the “real” chord.
“Jack Straw” by the Grateful Dead begins by serenely alternating E and Esus4.
Sus2 chords
This is the same idea as sus4, but now you’re lowering the third to the second. It is difficult to tell sus2 and sus4 chords apart by ear, because they both combine a whole step and a perfect fourth, just in different orders.
“Purple Rain” by Prince begins with a wistful Bsus2.
“What I Am” by Edie Brickell is a loop of Bsus2, Dsus2 and Asus2.
The second chord in “Love Song” by Sara Bareilles is Bbsus2.
“Free Fallin'” by Tom Petty uses a sus2 and a variant on sus4. The first chord is F. The second chord is Bbsus2. The third chord is C(add4), that is, C, E, F, G. This is not Csus4, the E is still in there! Typically you don’t use both the third and the fourth in a chord, they rub hard against each other. But Tom Petty clearly liked the tension.
Add2 and add9 chords
These are similar to sus2 chords, but rather than replacing the third with the second, you insert the second alongside the third. (Ninths are the same thing as seconds, just up an octave.)
I have seen the add2 chord described as dissonant, because it’s a cluster of whole steps. The chord doesn’t feel particularly tense in most pop contexts, though. Maybe that’s because it uses four out of the five notes in the major pentatonic scale, and we are used to that sound being a friendly and consonant one.
“Champagne Supernova” by Oasis begins with a long A(add9). I find these guys extremely irritating, but they did give us a useful music theory example.
In “Once in a Lifetime” by Talking Heads, the burbling atmospheric synth plays the notes G, A and E over a D chord backing. You could call this D(add2 add4).
Sixth chords
These should maybe be called add6 chords, because you’re taking a major triad and adding the sixth on top. (Classical music uses the term “sixth chord” to mean something completely different.)
My students describe this chord as a warm and sunny sound. Like the sus2 chord, it uses four of the five notes in the major pentatonic scale.
“She Loves You” by the Beatles famously ends on G6 rather than the expected plain G. The second to last chord is C, and George sings its third, E. Then when the chord changes to G, he continues to sing E, turning it into G6. Very hip.
Mulatu Astatke plays Eb6 for the entire duration of “Tezeta”.
The first four chords of “Us and Them” by Pink Floyd are D(add2), D6, Dm(maj7) and G/D. It’s a lovely combination.
6/9 chords
If you add a ninth on top of a sixth chord, you get this sunny yet enigmatic sound. Adam Neely explains its importance in jazz.
The 6/9 chord is magical for a couple of reasons. First of all, C6/9 comprises the entire C major pentatonic scale. Second, you can build it with a stack of perfect fourths: E to A to D to G to C.
Bossa nova uses lots of 6/9 chords. The Getz/Gilberto recording of “The Girl From Ipanema” by Antonio Carlos Jobim starts on Db6/9.
Mixolydian chords
7sus4 chords
These are easy to understand: you are taking a dominant seventh chord and replacing its third with a fourth. This creates a pleasing intervallic symmetry that you can see in the circular view.
People commonly use 7sus4 chords to jazz up their V7-I resolutions. When you play C7sus4 to F, it creates a softer landing, because C7sus4 already has F in it.
Prince starts off “Kiss” with E7sus4, resolving to A.
“Venus” by Shocking Blue starts on B7sus4, resolving to Em.
In “Pinball Wizard” by The Who, the main groove begins by alternating B7sus4 and B7, then moves to A7sus4 and A7.
Stevie Wonder uses an amazing chain of 7sus4 to 7 resolutions in the bridge of “Don’t You Worry ‘Bout A Thing“.
Ninth chords
These are like dominant seventh chords, but with the ninth on top.
“Ode To Billie Joe” by Bobbie Gentry begins on D9.
James Brown arpeggiates D9 at the end of the chorus in “I Got You (I Feel Good)”.
9sus4 chords
You make these by taking a ninth chord and replacing the third with the fourth. Check out the symmetrical structure.
Guitarists often play C9sus4 as Bb/C (a Bb major triad with C in the bass) or Gm/C (a G minor triad with C in the bass). It’s interesting to notice that the chord is built from the entire Bb major pentatonic scale or the entire G minor pentatonic scale.
“Maiden Voyage” by Herbie Hancock begins with D9sus4, then moves to F9sus4, then Eb9sus4.
Thirteenth chords
These big, dense chords use the entire Mixolydian mode except for the fourth/eleventh. As a practical matter, you can leave out other notes too; guitarists typically only play the root, seventh, third and thirteenth, in that order.
In James Brown’s funk classic “Get Up (I Feel Like Being a) Sex Machine”, guitarist Catfish Collins alternates Eb9 and Eb13 throughout the main groove. He voices the Eb9 with B-flat on top, and you can clearly hear that note alternating with the C on top of Eb13.
There is yet one more Mixolydian chord which I didn’t feel like diagramming out, and that is the 13sus4 chord. It’s a 13th chord with a suspended fourth, as the name implies. You can hear A13sus4 right before the first verse of “September” by Earth, Wind and Fire. You could also think of it as Gmaj7/A.
Dorian mode chords
Minor 9th chords
As the ninth chord is to the seventh chord, so the minor ninth chord is to the minor seventh chord. The major seventh interval between the third and ninth creates a poignant tension.
“Lonely Woman” by Horace Silver uses lots of prominent Ebm9 chords.
I didn’t feel like making a diagram, but you can extend minor ninth chords to minor eleventh chords by adding (you guessed it) the eleventh. Horace Silver ends the melody of “Song For My Father” on Fm11.
Minor 6th chords
The minor version of the sixth chord. The tritone between the flat third and the sixth gives the chord its bluesy edge. The minor sixth chord is also very similar to the diminished seventh, but with a natural fifth rather than a flatted one.
Prince’s devastating guitar solo in “Kiss” begins by alternating Am7 and Am6.
In “Let’s Dance” by David Bowie, the second chord in the chorus is Bbm6. (The first chord is Bbm11.)
Minor thirteenth chords
This chord is technically the entire Dorian mode stacked up in thirds. However, the important notes in the chord are the root, third, seventh and thirteenth.
The main groove in “The Payback” by James Brown alternates Bbm13 and Bm13.
Phrygian dominant chords
Seven flat nine chords
The most dissonant possible note you could add to a C chord is D-flat, and that is exactly what this chord does. The chord almost always acts as a minor-key dominant chord; if you hear C7b9 in a jazz tune, you can expect it to resolve to Fm.
If you leave the root off of C7b9, you get E°7.
“Caravan” by Duke Ellington, played here by Thelonious Monk, begins with a long stretch of C7b9. It is technically a V7 chord that resolves to Fm, but it sustains for so long that it starts to feel like a very edgy tonic.
Here’s my interactive Noteflight explainer of all of the chords listed above.
This post does not even approach being an exhaustive list of all the chords that are used in jazz and related music. It also ignores the issue of chord voicing (the specific ordering and spacing of notes across octaves.) And it does not get much into the function or usage of the chords. But it should at least demystify some of the symbols on lead sheets and chord charts. If you want to go deeper, check out some jazz theory resources.
The circle diagrams in this post were made using the aQWERTYon – try it yourself!
Thanks for another theoretical goldmine! I’m just at the point in my nascent musical career where I’m learning many of these chords on piano in order to play jazz songs, and this is immensely helpful context (and could also inspire a few original compositions as I play around with all of these). I do have a recommendation for another sus4 chord example, also from the Grateful Dead: Days Between, the final song Jerry Garcia and Robert Hunter wrote, which beautifully adopts Gsus4 as the tonic before moving into a stately minor-key progression for each verse. It’s one of my favorite songs to play on the piano – evocative and heartbreaking in the best way.