Chord extensions

[bachevelle]

Please let me preface this question by saying that I do own several "theory" books, so I'm not looking to have someone else do my homework for me. Sometimes books, even the "good" ones can be irritatingly vague. So, the question at hand is are chord extensions that include accidentals such as #9, b13, etc... diatonic? Is that a function of stacking thirds? Example: C E G B (CMaj7, no?) Wouldn't that make D the 9, F the eleventh and so on? So, D# would be the #9 thusly adding chromatic notes to the chord? Be gentle, I already know that I'm a moron.:)

[JonR]

Please let me preface this question by saying that I do own several "theory" books, so I'm not looking to have someone else do my homework for me. Sometimes books, even the "good" ones can be irritatingly vague. So, the question at hand is are chord extensions that include accidentals such as #9, b13, etc... diatonic? Is that a function of stacking thirds? Example: C E G B (CMaj7, no?) Wouldn't that make D the 9, F the eleventh and so on? So, D# would be the #9 thusly adding chromatic notes to the chord? Be gentle, I already know that I'm a moron.:)Well, I wouldn't know about that, but your question is intelligent... ;)

Chord symbols are a shorthand, and - as such - are based on the most common kinds of extensions - which may not always be diatonic, because chords are named independently of any key context. (It would be crazy if we had to name chords according to what key they were in...at least in jazz and rock it would. It makes more sense to do that in classical music, where figured bass chord signs are dependent on key.)

The plain numbers in chord symbols refer to the following intervals, as found on the indicated chords in a major key:

7 = minor 7th (as found on ii, iii, V, vi and vii)
9 = major 9th (I, ii, IV, V, vi)
11 = perfect 11th (I, ii, iii, V, vi, vii)
6/13 = major 6th/13th (I, ii, IV, V)

These can be altered as follows:

maj7 = major 7th
b9 = minor 9th
#9 = augmented 9th
#11 = augmented 11th
b13 = minor 13th

- and 5ths can be diminished (b5) or augmented (#5) too.

These are all still independent of key - always referring to the same intervals from the chord root.

IOW, "C7" always has a Bb, whatever key you see it used in.

"Am6" always has an F#, whatever key you see it used in.

"Fmaj7#11" = F A C E B. In the key of C, the #11 is diatonic. It's not called "Fmaj7/11" or "Fmaj11", because that would indicate a Bb. (And anyway, perfect 11ths are not added to maj7 chords.)

"Bm7b5" = B-D-F-A. All diatonic in key of C.

"E7b9" = E-G#-B-D-F. All diatonic to the key of A minor. (A harmonic minor scale.)

But the chords always have the same notes, wherever you see them.

With altered dominant 7th chords, the alterations may not come from a specific scale.
Eg "C7#9" = C-E-G-Bb-D#. There is no orthodox scale that contains all these notes. The chord generally works as a dom7 (V7) in F minor, where the D# represents Eb (b7 of key), while the E represents the leading tone. (In jazz they alter the 5th as well - or remove it - and invent a scale that does fit: the "altered" scale: C-Db-D#-E-F#-G#/Ab-Bb.)
C7#9 can also work as a tonic in a C blues, where (again) the Eb is the minor 3rd, set against the lower major 3rd, representing the ambiguous 3rd of blues scale. (It's known as the "Hendrix chord" in this usage.)


One way you can look at it is to assume that all chords are drawn from the mixolydian scale of the root note:
major 3rd, perfect 5th, minor 7th, major 9th, perfect 11th, major 13th.
Those extensions are either assumed (not specified in the symbol) - as with 3rd and 5th - or represented by plain numbers, indicating additions to the triad.

Eg, "C13" = C-E-G-Bb-(D)-A (9th is optional; 11th (F) usually omitted).
"C" means C major triad. "13" means major 6th (A) added on top of minor 7th (Bb).

Changes to that basic scale - lowering or raising notes by a half-step - are represented by additional signs in the chord, as follows:
"m" = lower the 3rd (nothing to do with the 7th)
"maj7" or "maj" = raise the 7th (nothing to do with the triad. You can have a maj7 on a minor chord)
"b9" = lower the 9th
"#11" = raise the 11th
etc, etc.

NB: chord symbols were not designed this way (based on mixolydian). It just looks like that. ;)

[jessmanca]

Please let me preface this question by saying that I do own several "theory" books, so I'm not looking to have someone else do my homework for me. Sometimes books, even the "good" ones can be irritatingly vague. So, the question at hand is are chord extensions that include accidentals such as #9, b13, etc... diatonic? Is that a function of stacking thirds? Example: C E G B (CMaj7, no?) Wouldn't that make D the 9, F the eleventh and so on? So, D# would be the #9 thusly adding chromatic notes to the chord? Be gentle, I already know that I'm a moron.:)

What JonR said.

Let me add that you're on the right track, and you can consider the chords to be diatonic based on their home key, or stand-alone chords, how you think about them doesn't really matter as long as you have what they're made of straight in your mind.

G9 would be diatonic in key of C, but chromatic in F because of the B natural. In either case it's still called G9 though.

b9 always refers to a note a minor 2nd (usually raised an octave to a minor 9th) above the root regardless of key.
#9 always refers to a note a minor 3rd above the root regardless of key.
#11 always refers to a tritone from the root regardless of key.
b13 always refers to a minor 6th above the root regardless of key.

They are all stand-alone, however you can choose to think of them in terms of the modes they are derived from.

b9 is from phrygian, locrian or the fifth mode of harmonic minor. It works well over a V chord in a minor key. Use sparingly.
#9 I think is really a "split 3rd" (adding both a minor and a major 3rd to a chord) You can think of this as derived from a blues scale. Works well on a I or V chord in blues.
#11 is derived from Lydian or Blues. Works well over a I or V chord in blues, and a IV chord in major. Also functions as a b5 over a diminished chord, etc.
b13 is diatonically from: aeolian, phrygian, locrian, and harmonic minor. It's another tension that is usually used over a V chord in minor or "altered chord." Also functions as a #5 over an augmented chord. Use sparingly.

Pretty much the same thing JonR said, just thought I'd try and clarify your confusion of whether the chords were diatonic or not.

Remember too that G13 doesn't imply that you play the 9th and 11th as well, you would only play the root, 3rd, 5th, 7th, and 13th. GBDFE. A chord with both a 9th and a 13th is called either G6/9 or G139.

In jazz you can add your own extensions if none are specified, and I would stick to diatonic extensions (to the current key) until you are familiar with where to use chromatic extensions.

[ChrisJ]

b9 always refers to a note a minor 2nd (usually raised an octave to a minor 9th) above the root regardless of key.
#9 always refers to a note a minor 3rd above the root regardless of key.
#11 always refers to a tritone from the root regardless of key.
b13 always refers to a minor 6th above the root regardless of key.

b9 is from phrygian, locrian or the fifth mode of harmonic minor. It works well over a V chord in a minor key. Use sparingly.
#9 I think is really a "split 3rd" (adding both a minor and a major 3rd to a chord) You can think of this as derived from a blues scale. Works well on a I or V chord in blues.


Not really: #9 is not a minor 3rd, it is an augmented 2nd. 3rds and 9th are different things as 3rds and 9th are usually both present in the chord and scale. Both major and minor thirds do show up in blues but for jazz we are talking about the altered scale and the chords derived from it: 1-b2-#2-3-b5-#5-b7 (you can call the b5 a #11 if you want. Although a lot of people write b13, I am more inclined to call it a #5 at least for dominant chords. A b6 or b13 would be logical for a minor chord derived from the aolian mode as it has a natural 5th (as in min7b13): Aolian: 1-2-b3-4-5-b6-b7.

You don't see b13ths and natural 5ths in dominant chords therefore #5 seems better. It also seems a lot easier to think of the altered extensions as b5,#5,b9,#9 rather than #11s and b13s. Altered chords come from the altered mode from melodic minor.

I agree that chords can't be named according to the key of the music they show up in but I think all chords have a scale that they come from. It is not a random thing. I can't really think of a chord that doesn't have a scale.

JonR: 1-3-5-b7-#9 would come from the half/whole diminished scale (orthodox I'm not sure). Although it is also a Blues type thing as well and Blues defies logic (sort of).

If you know tha scale you know the chord:

Altered: 1-b2-#3-b5-#5-b7 = 7(b5,#5,b9,#9)
Half/Whole Diminished: 1,b2,#2,3,#4,5,6,b7 = 13b9 or 13#9
Mixolydian: 1-2-3-4-5-6-b7 = 7, 9, 13, 7sus4 etc..

Check this to see how scales and chords work together:
http://chrisjuergensen.com.hosting.domaindirect.com/scaleformula.htm

and chord formulas:
http://chrisjuergensen.com.hosting.domaindirect.com/chordformula.htm

-CJ

[Jed]

You don't see b13ths and natural 5ths in dominant chords therefore #5 seems better.

small point, and possibly nit-picking but

THe Melodic minor's V7 chord scale = 1 2 3 4 5 b6 b7.
The Harmonic minor's V7 chord scale - 1 b2 3 4 5 b6 b7.

So there is at least two examples of a natural 5th with a b13. We cannot assume that all dom b9 or dom #9's refer to the altered scale.

[JonR]

Not really: #9 is not a minor 3rd, it is an augmented 2nd. 3rds and 9th are different things as 3rds and 9th are usually both present in the chord and scale. Both major and minor thirds do show up in blues but for jazz we are talking about the altered scale and the chords derived from it: 1-b2-#2-3-b5-#5-b7 (you can call the b5 a #11 if you want. Although a lot of people write b13, I am more inclined to call it a #5 at least for dominant chords. A b6 or b13 would be logical for a minor chord derived from the aolian mode as it has a natural 5th (as in min7b13): Aolian: 1-2-b3-4-5-b6-b7.
All agreed.
However, my feeling is - regarding 7#9s as minor key Vs - that they sound right in that context because the #9 echoes the b7 of the key (which would be the b3 of the chord). The chord kind of has it both ways: leading tone of harmonic/melodic minor, along with the b7 of natural minor. (That's just my alternative way of hearing it/looking at it ;) )
But in terms of the associated improvisation scale, it's quite correct to talk about b2 and #2, not b3.
I have seen chord charts (some years back now) that wrote the chord as "7b10" - but I think there's general theoretical agreement now that a chord should only have one of each note. So it must be #9.
(Of course, scales are also supposed to only have one of each note. The altered scale is an exception - unless you think of it as superlocrian: 1-b2-b3-b4-b5-b6-b7.)

Maybe if you were using the HW diminished scale on a 7#9, you could argue for b3/b10, because you have 8 notes in that scale anyway, one has to double up somewhere: 1-b2-b3-3-#4-5-6-b7. ;)
Speaking of which...

JonR: 1-3-5-b7-#9 would come from the half/whole diminished scale (orthodox I'm not sure). Yes - I should perhaps have said no "diatonic" scale, rather than no "orthodox" scale.
In fact, my view is that the dim scale is a synthetic creation designed to fit the chord. Not vice versa.
Same with dim7 chords. Originally they derive from the vii degree of harmonic minor. But jazz theory assigns the WH dim scale to them, because it has no "avoid notes", and because its symmetry suits the functional ambiguity of dim7s.
The HW dim scale then gets applied to 7b9s (or 7#9s) because of the close association between dim7s and 7b9s.
(In A harmonic minor, E7b9 (V) and G#dim7 (vii) are essentially the same thing.)

If you know tha scale you know the chord:

Altered: 1-b2-#3-b5-#5-b7 = 7(b5,#5,b9,#9)
Half/Whole Diminished: 1,b2,#2,3,#4,5,6,b7 = 13b9 or 13#9
Mixolydian: 1-2-3-4-5-6-b7 = 7, 9, 13, 7sus4 etc..Agreed!
And don't forget wholetone: 1-2-3-b5-#5-b7 = 9b5, 9#5
;)

[ChrisJ]

Jed: Yes, that is very true. Probably what I meant to say is that although there are scales which contain both the b6 and 5 (like the mixo b6 scale from melodic minor), you don't see them together in dominant chords. If I were to write a 7#5 chord as a 7b13 chord, it implies that there may be a natural 5th in the chord which would be strange.

Good point.

JonR: Wow, never imagined the H/W Diminished scale manufactured to fit the chord. It seems like such a logical scale to build chords from! I would have assumed it the same as most other scales. Chicken or egg kind of thing.

-CJ

[JonR]

small point, and possibly nit-picking but

THe Melodic minor's V7 chord scale = 1 2 3 4 5 b6 b7.
The Harmonic minor's V7 chord scale - 1 b2 3 4 5 b6 b7.

So there is at least two examples of a natural 5th with a b13. We cannot assume that all dom b9 or dom #9's refer to the altered scale.Good point.
In practice, however, whenever I've ever seen a 7b13, it's implying the altered scale. (If I'd ever seen "9b13" - and I don't think I have - that would be less ambiguous.)

Mark Levine (Jazz Theory Book) states that 5th mode of melodic minor is rarely used, and "chords built off the 5th mode of melodic minor function as tonic minor chords" (p.66) - IOW 2nd inversion minor tonics.
He gives an example from a Wayne Shorter tune of a D major chord reharmonised as what he calls "Gm(maj7)/D". (The voicing he shows is D-Bb-D-F#-A, which intriguingly has no G. Still - he implies - G is the natural root of the chord. It's also worth noting that the Bb is voiced below the A.)

As for harmonic minor, he deigns to give it no more than 3 pages (out of 500+), right at the end of the book, before 2 pages on harmonic major. This is because he regards it as - at best - peripheral to jazz theory, because the great players barely used it. (He managed to find just 2 examples.) Where you might think harmonic minor would fit (ii-V-i in minor key), they would always choose something else (diminished, modes of melodic minor, etc).

[Danster]

You guys are either awesome, or you're nerds, I'm not sure which. :D :D :D

[Jed]

You guys are either awesome, or you're nerds, I'm not sure which. :D :D :D

Well ChrisJ and JonR are awesome, . . . me I'm just an awful nerd with no life.

Chris,

Of course you are right (I've never seen you wrong!). It's almost a mute point for guitarists since I can't think of a case where we would want to play both the natural 5th and the b6 harmonically in the same voicing. Of course from a larger musical perspective these issues carry somewhat greater weight. . . . It's just me splitting hairs . . . it's a bit of a hobby for me.

I do take great care to distinguish #5 from b13 based on what I believe the scale to be, but my logic for determining the scale is based on melody / what my ear hears rather than common practice or any particular scale.

Jon,

I have no doubt that accepted practice is what Levine covers in his material. I unfortunately have to sort out all these things for myself the hard way since, although I normally learn easily from books, . . for music I seem to have to learn everything the hard way and in gory detail. So I haven't really gotten to the point where my thoughts on the minor scale variations are well prioritized or organized. So many variations of the wheel to re-invent . . .

cheers,

[ChrisJ]

I'm sort of an undercover nerd.
-CJ

[ChrisJ]

I'm sort of on subject here. I found this cool composition gererator on the internet. The compositions themselves are sort of simple but you can choose from countless scales that I have never heard of. Indian and synthetic scales. Some interesting choices like Chromatic Lydian Inverse?? and Prokofiev?? Promethius Neopolitan??? It is a good tool to learn some interesting sounds.

If you mess around with it you can create some pretty cool sounds:
http://tones.wolfram.com/generate/advanced.html?pitch

-CJ

[JonR]

You guys are either awesome, or you're nerds, I'm not sure which. :D :D :DWe're both. The awesomest nerds you ever saw...
:D

[JonR]

Jon,

I have no doubt that accepted practice is what Levine covers in his material. I unfortunately have to sort out all these things for myself the hard way since, although I normally learn easily from books, . . for music I seem to have to learn everything the hard way and in gory detail. So I haven't really gotten to the point where my thoughts on the minor scale variations are well prioritized or organized. So many variations of the wheel to re-invent . . .

cheers,My feeling exactly.
[Scratches beard, leans back on creaky rocking chair, spits on nearby dog.)
I learned it all the hard way too. By - er - actually playing and improvising, copying blues and folk players, picking up the habits of the genre. It wasn't until many years later I started reading about theory - out of curiosity - and many years after that I encountered such things as "scale patterns", "tab", "melodic minor", and - gasp - "modes"... Oh brave new world that has such things in’t! (to misquote our Will) :rolleyes:
I'd been playing jazz some years before I picked up Levine's book. And another few years before I "got" a lot of the concepts.
Eg, the altered scale took me some time. It wasn't until I could find some easy-to-apply patterns (superimposed arpeggios, pentatonics or licks) that I could actually use it. And I understood it as chord tone variants and voice-leading. That didn't come from Levine, that came from practical experiment.
IOW, the theory (to some extent) pointed a new way, but I had to PLAY my way into it before it made any sense.
I still haven't finished his book, and I still don't (much) use the concepts in playing. I play much the way I always did - off chord tones, using blues licks, and stuff I learned from Broonzy and Chuck Berry (which amount to a mix of major and minor pent, in the terminology I learned much later). Old habits die hard. (I'd like to be able to sound like Wes, but I still prefer Big Bill, to be honest...)
The difference now is I can talk about what I'm doing and sound educated. :D
(Trouble is, I end up talking about what I ought to be doing, instead of doing it...)