NEW INTERVALS:
9th: 14 Semitones
11th: 17 Semitones
13th: 21 Semitones
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We already know how to work out the seven seventh chords. For example, If I ask you what Cmaj7 is, you should be able to reply, "C E G B". However, unlike seventh chords, which have many types depending on the situation, ninth, eleventh and thirteenth chords are classed as extended chords and are a lot easier.
No matter what situation you're in, A ninth chord will just be an extra note 14 semitones above the root note of a seventh chord. Cmaj9 is C E G B D. Cmin9 is C Eb G Bb D, Caug9 is C E G# B D, Cdim7 is C Eb Gb A D. The fifth note will always be the same 14th semitones away from the root note, unless the chord itself tells you otherwise.
An eleventh chord works on the same principle. Just take a ninth chord and add another note 17 semitone from the root note. A thirteenth chord is just an eleventh chord with an extra note 21 semitones from the root note.
So:
Cmaj13: C E G B D F A
Cmin13: C Eb G Bb D F A
Caug13: C E G# B D F A
C13: C E G Bb D F A
Cminmaj13: C Eb G B D F A
Chalf-dim13: C Eb Gb Bb D F A
Cdim13: C Eb Gb A D F A
No matter the situation, the 9th is always 14 semitones, the 11th is always 17 and the 13th is always 21 semitones unless the chord says otherwise. Speaking of which:
Altered Chords:
We've just learnt that Cmaj11 is C E G B D F. However, what would the chord Cmaj11b9be? It would be C E G B Db F, as the chord tells us to flat the 9th.
Cmaj13b9 b13 would be: C E G B Db F Ab, as the chord tells us to flat the 9th and 13th.
Activity: COMPLETE THE CHORDS:
1) Eaug13b11: ________________________
2) Dmin11: __________________________
3) G#dim13b9,b11,b13: ___________________
4) Fmaj9: ____________________________
5) Dbmaj11#9: ________________________
6) C E G# B D# F: ______________________
7) C Eb Gb A D F# A#: __________________
8) Bmin13#9,b11,#13: _____________________
9) G#halfdim13b9,b11,#13: __________________
EVEN WEIRDER CHORDS:
Slash Chords:
A slash chord will look like something like this: C/e. The top note represents a chord. The bottom note is the note to be played at the bottom. For example, C/e would be E(3),C,E(4),G4. It's just an e on the bottom of a C chord. D/f would be a Dmin chord with an F played at the bottom.
Here's when things start to get weird: C/b. If you rearrange this and uninvert it, You're playing a Cmaj7 chord in third inversion. This is weird because it's no longer a c harmony, it is a Cmaj7 harmony, yet you still need to make good voicing decisions and what chords to use next, which can mess you up.
Polychords:
A polychord will look something like this:
Bb
--
Cm
It is a Bb maj chord over a C minor chord. Now, both the notes represent chords. In reality, you're just playing a Cmin11. The only problem with this is you're not being told the harmony at all, and if you don't you run the risk of making some poor decisions figuring out how to use your chord progression.
Sixth Chords:
A sixth chord just looks like this: x6. For example, C6. A C6 would be C,E,G,A. Cm6 would be C,Eb,G,A. The C6 chord is simply a Amin7 chord in first inversion, so why use C6 instead of Amin7 in 1st position? I don't know, to be honest. Perhaps there is a method in the madness, especially in jazz.
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Music theory + Composition Technique (FREE!)
Non-FictionThis book contains information on basic music theory for those wanting to introduce themselves to music and composition. It includes exercises and practices to help you learn quickly, all for free.
