We finish our series on chords and chord symbols by looking at extended chords. These are chords whose names include numbers higher than 8, like CMaj9, G13, and Dmin11.

As we learned last time, the 9th of a chord is the same tone as a 2nd. That is, the 9th of a C chord is D, a maj 9th (or maj. 2nd) up from the root, C. The 11th is the same as a 4th, and the 13th is the same as the 6th. To get the lower "version" of an extension, just subtract 7: 9 - 7 = 2, 11 - 7 = 4, 13 - 7 = 6.

But how do you know whether to call a D in a C chord a 2 or a 9? It depends on the rest of the chord. If the chord has a third (E), then the D is a 9; if the D takes the place of the third (as in a Csus2 chord), then it's a 2. Also, the 9 can imply the 7 as well: a CMaj9 chord is CMaj7 with a 9 (D) added; C9 is C7 with a 9 added; and Cmin9 is Cmin7 with a 9 added. In the "sus2" chord mentioned above, the 2 replaces the 3, and ther's no 7: Csus2 is C, D, and G (no E).

What about an F in a C chord, is it an 11 or a sus4? Again, it depends on the rest of the chord. The sus4 tone takes the place of the 3rd: Csus4 is C, F, and G. But the 11th doesn't, which means there's still a 3rd. If it's a maj 3rd, the 11th sounds very dissonant against it, so we generally avoid 11's in maj. and dom. chords (except sharp-11's — see below). But 11's sound great in minor chords because they don't clash with the 3rd. Minor 11th chords also have 9th's and 7th's, so think of Cmin11 as a Cmin9 with an 11 added: C, E-flat, G, B-flat, D, and F.

(NOTE: Last month I said that Maj7 chords rarely have a sus4. It's not that you can't play it, but in terms of reading lead sheets, song books, etc., you will almost never see a Maj7sus4 chord symbol. This is because certain assumptions are built into these symbols; one such assumption is that Maj7 chords usually don't have a sus4, because of the tritone created between the 7th and the 4th.)

The 13th is used in dom7 chords (the same tone in maj. and min. chords is called a 6th, usually replacing the 7th). 13th chords have 9th's and 7th's, but no 11th's (because of the clash between 11th's and maj. 3rd's — see above). C13 is C, E, G, B-flat, D, and A (no F).

The tones in extended chords can be arranged in whatever order you choose, but certain voicings are more common. One of the extensions is often voiced on top to make it ring out more clearly, but they can also add richness and density voiced lower down.

Chords often have altered tones such as "flat-9," "sharp-9 (AKA "+9"), "flat-13," etc. Usually they're used in dom7 chords: C7(flat 9), C13(flat 9), etc. "Flat-9" means the 9th of the chord has been lowered one half-step: C7(flat 9) has a D-flat instead of a D. "Sharp-9" raises the 9th a half-step: C7(sharp 9) is C, E, G, B-flat, and D-sharp. "Flat-13" lowers the 13th a half-step: C7(flat13) is C, E, G, B-flat, D, and A-flat. Alterations can be combined, e.g. C7(flat9, flat13) is: C, E, G, B-flat, D-flat, and A-flat. C+7(sharp9) is C, E, G-sharp (indicated by "+"), B-flat, and D-sharp.

Common alterations on Maj7 chords are sharp-11 and flat-5. In Maj7 chords, the flat-5 is actually spelled as a sharp-11; for example, in CMaj7(flat-5), the flat-5 is actually spelled as an F-sharp — one of the quirky inconsistencies of chord notation as it's evolved over the years. In CMaj7(#11), the sharp-11 is also F-sharp. So, why the distinction? In a Maj7(flat-5) chord, the sharp-11 takes the place of the fifth; in a sharp-11 chord, the fifth may still be present. Also, remember, the 11th (and sharp-11th) implies the 9th. But a flat-5 chord has no 9th (unless the chord symbol has a 9). CMaj7(flat-5) is C, E, F-sharp, and B. But C Maj 7(sharp-11) is C, E, G, B, D, and F-sharp. Unlike regular 11's, sharp-11's don't clash with the maj 3rd. Sharp-11's and flat-5's also sound great on dom7 chords. C7(sharp-11) is C, E, G, B-flat, D, and F-sharp. C7(flat-5) is C, E, F-sharp, and B-flat.

A less common alteration on Maj7 chords is the sharp-5. CMa7(#5) is C, E, G-sharp, and B.

Sometimes a minor chord will have a maj 7th instead of a min 7th. For example, Cmin(maj7) chord is C, E-flat, G, and B-natural (rather than B-flat). It's a lovely, haunting sound.

Altered chords allow for more chromatic voice leading, but they can also be used for their own unique qualities without resolving to some other chord. In pop music, the most common example is the dom7sharp9 chord — Hendrix's "Crosstown Traffic" features it prominently.

Work with a good music theory book and/or a good teacher to learn how extended and altered chords work. Enjoy!


Copyright 2000 by Richard Middleton.
All rights reserved.