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Terminology for sixth and ninth chords

5K views 33 replies 7 participants last post by  millionrainbows 
#1 · (Edited)
As I mentioned elsewhere, I've just been experimenting with writing in a jazz idiom, and I'm finding some of the chord terminology quite confusing. I'm used to the terminology for seventh chords:
  • a plain "seventh chord" (e.g. C7) is a major triad plus a minor seventh
  • a "minor seventh chord" (e.g. Cm7) is a minor triad plus a minor seventh
  • a "major seventh chord" (e.g. Cmaj7) is a major triad plus a major seventh
  • a "diminished seventh chord" (e.g. Cdim7) is a diminshed triad plus a diminished seventh

So far, so good. But when you get to sixths and ninths the terminology can be quite counter-intuitive. For example:
  • a "minor sixth chord" (e.g. Cm6) is a minor triad plus a major sixth
  • a "minor ninth chord" (e.g. Cm9) is a minor triad plus a minor seventh and a major ninth

You'd expect a so-called "minor sixth" or "minor ninth" chord to include the interval of that name, but it doesn't. The "minor" part refers to the triad and the "sixth" or "ninth" part is major by convention, apparently.

To confuse things still further, a "dominant minor ninth" chord actually does contain a minor ninth - it's a dominant seventh plus a minor ninth (written C7b9 or C7-9). So a "donminant minor ninth chord" isn't a type of "minor ninth chord"!

Is this terminology used in classical music as well or is it unique to jazz and popular music? I find it horribly confusing and would like to know how it originated.
 
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#2 ·
Don't sweat it, Guy. All of what you said is correct, but jazz/pop chord theory is totally different than Classical music traditional theory. How is it different? Well, traditional Classical music theory is rooted in chord relationships in a key. Pop/Jazz chords ignores relationships and just says play this chord regardless of how it may or may not relate to the key. How did it evolve? I'm not sure but clearly simplicity was a driving factor.
 
#32 ·
... Pop/Jazz chords ignores relationships and just says play this chord regardless of how it may or may not relate to the key...
As a former life-long jazz musician, I haven't found this to be exactly true that there's a lack of chordal relationships in jazz harmony, though some compositions will not necessarily modulate logically from one chord to another, but will jump from one chord to another in some type of a seemingly random but still repeated pattern.

What I've found that helps in the study of chords and chord notation is to isolate those tones that make for the altered chord. In the matter of a C7-9, it's still a major chord with a flat 9 and its essence can be heard using the scale of C, Db, E, F, G, A, and Bb. The key matter is to determine the scale upon which any chord is built. In the matter of a Cm7-9, its scale would consist of C, Db, Eb, F, G, A and Bb. Also note the melody over the chord, because it will help determine the exact scale the altered chord is based on.

I also highly recommend the great jazz vibe player Gary Burton's teachings on improvising and jazz harmony in which he clearly explains the details of what I've tried to share and the importance of determining the scale that any altered chord consists of:
 
#9 · (Edited)
You need to make the distinction between a chord name (what it is called orally) and chord designation, how it is written.

A jazz "chord name" like "minor sixth" does not really apply in classical theory, since classical deals with minor/major/diminished/augmented/seventh/ninth chords and does not specify alterations or upper extensions past the ninth, to my knowledge.
 
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#4 ·
Well, first for Classical theory, the chord has to "exist" in a specific key either as a "diatonic" chord or a standard "chromatic" chord and then assigned Roman numeral analysis. Pop chord symbols are not used; so one can't call it Cm6. You also can not use an added sixth as part of Roman numeral analysis. Added seconds, fourths and sixths were not used until the 20th Century so they fall out of the range of traditional Roman numeral labeling. Thus if you were in the key of B-flat major, the Cm6 chord would exist only as a vii half-diminished chord (A, C, E-flat, G) in first inversion (the bass note being "C").

So you can see jazz/pop chord analysis is way different than Classical.
 
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#5 ·
Another difference between jazz and classical theory is that classical nomenclature is based on function and jazz nomenclature is largely descriptive — which I think is a different way of saying the same thing Vasks did. For example, jazz theory doesn't distinguish between chords of the augmented 6th and dominant 7th chords — they tend to get lumped together as so-called tritone substitutions for one another.
 
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#6 · (Edited)
Thanks for the above comments. I suppose I was wondering more about the names of the chords rather than the notation for them. For most of the chords that I've used up until now, the names of the chords in jazz and popular music are the same as in classical music: major, minor, augmented, diminished and the various types of seventh chord. You also get things like suspended fourths which appear to be the same. It's only when you get on to sixth and ninth chords that the terminology appears to diverge. As already pointed out, a chord like C-E-G-A could only be analysed in classical theory as the first inversion of a minor seventh chord.

I suppose each genre of music is likely to adopt terminology that's suited to that particular genre. It's just a shame from my point of view that jazz has decided to use terminology for chords that's at odds with the established terminology for intervals.
 
#7 · (Edited)
I believe that in classical music C-E-G-A, when it is a final chord, is occasionally analyzed as a major chord with an added 6th. If memory serves, this occurs in Mahler's Das Lied von der Erde?

I view it not as a shame, but as more of a purely practical matter that in jazz, for example, C-E-G-A is described as a major 6th chord rather than as a first inversion minor seventh chord. It is simply more concise to write C∆6 than to write Am7/C.
 
#8 ·
As I mentioned elsewhere, I've just been experimenting with writing in a jazz idiom, and I'm finding some of the chord terminology quite confusing. I'm used to the terminology for seventh chords:
  • a plain "seventh chord" (e.g. C7) is a major triad plus a minor seventh
  • a "minor seventh chord" (e.g. Cm7) is a minor triad plus a minor seventh
  • a "major seventh chord" (e.g. Cmaj7) is a major triad plus a major seventh
  • a "diminished seventh chord" (e.g. Cdim7) is a diminshed triad plus a diminished seventh

So far, so good. But when you get to sixths and ninths the terminology can be quite counter-intuitive. For example:
  • a "minor sixth chord" (e.g. Cm6) is a minor triad plus a major sixth
  • a "minor ninth chord" (e.g. Cm9) is a minor triad plus a minor seventh and a major ninth

You'd expect a so-called "minor sixth" or "minor ninth" chord to include the interval of that name, but it doesn't. The "minor" part refers to the triad and the "sixth" or "ninth" part is major by convention, apparently.
Drop the interval thinking.
Firstly, designate a chord by its quality: major or minor, which refers to its third.

Secondly, designate whether it is a seventh chord or not:
Designate it a "seventh" chord if it has a flatted seventh. Call it a "major seventh" if it has a major seventh.

Examples:
CM7 is C-E-G-B. (C major seventh)
Cm7 is C-Eb-G-Bb. (C minor seventh)
Cm/M7 is C-Eb-G-B. C minor/major seventh)

To confuse things still further, a "dominant minor ninth" chord actually does contain a minor ninth - it's a dominant seventh plus a minor ninth (written C7b9 or C7-9). So a "donminant minor ninth chord" isn't a type of "minor ninth chord"!
Don't call it that, then: call it a C7 flat nine.
It is a "dominant " chord because it is a 7 chord, meaning flatted seventh.
After that, designate its ninth, and whether it is altered.

Example:
C9 is a C major with a flatted 7 and a ninth: C-E-G-Bb-D. The 7th is understood. You could say C7/9 if you wanted. But not C7-9, because the dash (-) means minor.

Some like to use the dash to denote minor chords: C-7 means C minor with a flatted seventh. I don't. I prefer Cm7.

Is this terminology used in classical music as well or is it unique to jazz and popular music? I find it horribly confusing and would like to know how it originated.
It's not confusing if you straighten your thinking out. You sound like you already know figured bass, which uses interval distances.
 
#10 ·
Don't call it that, then: call it a C7 flat nine.
It is a "dominant " chord because it is a 7 chord, meaning flatted seventh.
Well it's a dominant only if it goes to an F chord. But in jazz that C7flat9 might just go to any number of non-F chords.

Which is just one reason why trying to equate jazz chord designations with traditional theory does not work. Guy was just hoping there was a direct connection.
 
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#15 ·
Well, since the thread continues I'd like to add an observation. Yes, millionrainbow, the term dominant seventh chord is used in jazz to explain its construction. But think about how odd it is that the only traditional theory term for chord relationships used is the dominant seventh. There's no discussion of a supertonic, subdominant, etc. For me, the usage of the term dominant is to explain the chord's function/hierarchy in a key and yet in this instance it's not.
 
#17 · (Edited)
… when you get to sixths and ninths the terminology can be quite counter-intuitive. For example:
  • a "minor sixth chord" (e.g. Cm6) is a minor triad plus a major sixth
  • a "minor ninth chord" (e.g. Cm9) is a minor triad plus a minor seventh and a major ninth
I didn't directly address your specific cases in my last post. As I wrote above, the root of a Cm6 chord isn't C, it is A, a half diminished 7th chord. In general, inversions of 7th chords are called 6th chords.

9ths follow the same rule as 7ths noted above. If the 3rds and 7ths agree, one uses one iteration of either minor or major (C∆9, Cm9) and one adds a number understood to be diatonic in relation to the root. When the thirds in dominant chords don't agree, one writes (or assumes) a plain 7. So, C9 assumes a M3, m7, and diatonic 9th. Alterations of 9ths require flats or sharps.

Is this terminology used in classical music as well or is it unique to jazz and popular music? I find it horribly confusing and would like to know how it originated.
I would assume it evolved to meet the needs of players for unambiguous symbols that are as concise as possible. Survival of the fittest and most concise.
 
#25 ·
I'm in danger of just repeating myself in this thread, but I'll say it again slightly differently:

"Cmaj7" = "C" + "maj7"
"Cm6" = "Cm" + "6"

In the first one, you have to take the "maj" with the "7". In the second, you have to take the "m" with the "C". I regard that as an inconsistency. However, I'm happy to live with it.
 
#26 ·
I'm in danger of just repeating myself in this thread, but I'll say it again slightly differently:

"Cmaj7" = "C" + "maj7"
That's correct; it doesn't contradict anything I've said.

"Cm6" = "Cm" + "6"
"Cm6" = Cminor + "6" That's correct.

In the first one, you have to take the "maj" with the "7".
True; that's because it is designating an exceptional seventh, not the old dominant flat-seven.

In the second, you have to take the "m" with the "C". I regard that as an inconsistency. However, I'm happy to live with it.
No; remember, the flat-seven is the default seventh, designated as "7" with no need to qualify it as a minor seventh.

In "Cm6," there is no seventh. The "minor" therefore refers to the quality of the C chord, not a seventh or sixth.
 
#34 ·
The thing to remember about classical vs. jazz is that jazz musicians need clarity, and practical answers and solutions. Classical musicians do not; they simply follow the notation of what they play, and are not "paid to think". They are "paid to follow tradition."
 
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