Help Understanding Jazz Minor Blues

[Bryan R. Tyler]

Recently started working on the Aebersold play-along minor blues book, so bear with me as I'm new to this. While I can play along with it just fine, I'm interested in knowing why things are set up the way they are.

Using a Cm blues for example, it moves from Cm (which is stated as using a Dorian minor- is it more typical to use Dorian as a minor instead of a natural minor in jazz blues?), it moves up to C7+9 before going into Fm. I'm assuming the C7+9 is there for tension that's resolved with the Fm, correct? Either way, I still haven't gotten my ears around the sound of a diminished whole tone scale yet Now, is the Fm also supposed to be played as a Dorian? I know regular blues takes things of of the context of a key at the will of the composer, often having all the chords have a dominant 7, so I didn't know if this was common with jazz blues as well.

After going back down to Cm, the turnaround is written as D half diminished, a G7+9, and a Cm- so a II-V7-I but played as Locrian, diminished whole tone (I imagine this is interchangable with other dominant scales) and Dorian. It sounds nice, but I was wondering if someone could explain exactly why it works this way in the context of the key. Or should I basically ignore the key and just follow the chord changes?

[arcellus]

Originally Posted by Bryan R. Tyler

is it more typical to use Dorian as a minor instead of a natural minor in jazz blues?

Yes. In jazz, you can generally assume that a minor chord will want a Dorian scale, unless the chord symbol is more specific (ie, Cm7b13 would imply Aeolian) or a note in the melody is taken from a different scale - by the way, always look at the melody for answers to harmonic questions.

Originally Posted by Bryan R. Tyler

I'm assuming the C7+9 is there for tension that's resolved with the Fm, correct?

Yep.

Originally Posted by Bryan R. Tyler

Either way, I still haven't gotten my ears around the sound of a diminished whole tone scale yet

Also keep in mind that there are a lot of other scales you can use on an altered-dominant chord: H/W Diminished, Whole Tone, 5th mode of Harmonic Minor. The "+9" just indicates that the chord is altered - exactly how it's altered is up to you.

Originally Posted by Bryan R. Tyler

Now, is the Fm also supposed to be played as a Dorian?

Probably. Again, look at the melody for clues.

Originally Posted by Bryan R. Tyler

After going back down to Cm, the turnaround is written as D half diminished, a G7+9, and a Cm..

In my understanding, the chords don't really function in the context of the key here, at least not in a traditional sense. You could look at the Dm7b5 as the ii of an Cm7 Aeolian chord - if the C was Aeolian, the next chord up would be Locrian. But that's not really how it works, the chords are actually taken from different keys.

Also, you're not stuck with playing Locrian on that Dm7b5 chord either - try the 6th mode of the Melodic Minor scale. A lot of people call this the "Locrian, #2" scale - it's the same as Locrian with a raised 2nd degree - but I usually just call it the Half-Diminished Scale. Also try the 2nd mode of the Harmonic Minor scale or the W/H Diminished scale. Experienced improvisers mix these up at their whims

I hope this helps - and if anyone out there wants to correct me, please do. I don't think any of this is the definitive word!

[arcellus]

also check out the book "scales for jazz improvisation" by dan hearle. totally helpful.

[Richard Lindsey]

Originally Posted by arcellus

Yes. In jazz, you can generally assume that a minor chord will want a Dorian scale, unless the chord symbol is more specific (ie, Cm7b13 would imply Aeolian) or a note in the melody is taken from a different scale - by the way, always look at the melody for answers to harmonic questions.


Yep.


Also keep in mind that there are a lot of other scales you can use on an altered-dominant chord: H/W Diminished, Whole Tone, 5th mode of Harmonic Minor. The "+9" just indicates that the chord is altered - exactly how it's altered is up to you.


Probably. Again, look at the melody for clues.


In my understanding, the chords don't really function in the context of the key here, at least not in a traditional sense. You could look at the Dm7b5 as the ii of an Cm7 Aeolian chord - if the C was Aeolian, the next chord up would be Locrian. But that's not really how it works, the chords are actually taken from different keys.

Also, you're not stuck with playing Locrian on that Dm7b5 chord either - try the 6th mode of the Melodic Minor scale. A lot of people call this the "Locrian, #2" scale - it's the same as Locrian with a raised 2nd degree - but I usually just call it the Half-Diminished Scale. Also try the 2nd mode of the Harmonic Minor scale or the W/H Diminished scale. Experienced improvisers mix these up at their whims

I hope this helps - and if anyone out there wants to correct me, please do. I don't think any of this is the definitive word!

I would disagree to an extent. You do see the dorian with minor chords in jazz maybe more often than you would otherwise expect, but IME and IMO it's by no means the case that you should normally expect the minor to take the dorian in jazz. That's kind of an overstatement IMO.

Also, those chords DO function in the context of the key. It's practically a textbook ii-V-i in Cm. Somewhat disguised by the fact that the i is a i7, but the force of the progression is there nonetheless. The chords aren't really taken from different keys at all; they're pretty functional as is.

Finally, there's no particular reason you have to play a different mode/scale on every chord. You can, but you don't always have to. Often however, it may be better to think of several chords as inhabiting a single tonality or harmonic space; it can give a better sense of what's really happening harmonically.

Good point about the melody guidance; that tells you a lot about which way to go.

[Bryan R. Tyler]

Originally Posted by Richard Lindsey

Also, those chords DO function in the context of the key. It's practically a textbook ii-V-i in Cm. Somewhat disguised by the fact that the i is a i7, but the force of the progression is there nonetheless. The chords aren't really taken from different keys at all; they're pretty functional as is.

One thing that confuses me about that is that if a D half-diminshed fit into the same key, then wouldn't it have to ("have to" is obviously a loose definition in jazz I'm coming to find ) represent the 7th step and)the Cm have to represent the 6th step (Aeolean)?

[arcellus]

Originally Posted by Richard Lindsey

Also, those chords DO function in the context of the key. It's practically a textbook ii-V-i in Cm.

I guess I misspoke when I said "function." What I meant was that the ii and V aren't chords built from the scale of Cm, whether it's Aeolian, Dorian, or whatever is implied by the melody. But they are absolutely taken from different keys - where does the G7alt come from? Certainly not the same key as the Cm chord - which would be either Bb, Ab, or Eb.

And the idea of looking for common scales to fit over multiple chords is a great one. But what scale fits without being altered over all three chords in a minor ii/V/i?

[Bryan R. Tyler]

The chromatic one?

[arcellus]

ha.

by throwing out those other scales i was just trying to let you know that you've got options - explore 'em!

[Richard Lindsey]

Originally Posted by arcellus

I guess I misspoke when I said "function." What I meant was that the ii and V aren't chords built from the scale of Cm, whether it's Aeolian, Dorian, or whatever is implied by the melody. But they are absolutely taken from different keys - where does the G7alt come from? Certainly not the same key as the Cm chord - which would be either Bb, Ab, or Eb.

And the idea of looking for common scales to fit over multiple chords is a great one. But what scale fits without being altered over all three chords in a minor ii/V/i?

Some kind of altered scale or mode. Who said it couldn't be altered? Not me. Who said scales could only be the "straight" ones? You could, for example, use C harmonic minor with the minor 7 added in as a color/tension tone.

Besides, adhering to one scale for that progression is not exactly what I was getting at. What I was getting at was more the idea that when you have a progression like that, you don't have three little harmonic worlds, one moving to the next. What you have is three things functioning within a single harmonic world. That's actually the reason that progression is so strong and resolves so authoritatively. So it pays IMO to think of it that way. It helps you connect what you're doing from one chord to the next, to play through the changes rather than just on top of them one by one.

And a D half diminished can easily be built from Cm. It is in fact the prototypical ii7 chord in Cm; there's no note in it that doesn't exist in Cm. You can build it from either C aeolian or C harmonic minor. And a G7 alt is just a G7 with some 1000 Islands dressing on top. Again, if you wanted, you could think of that whole little harmonic space as a kind of C harmonic minor, with a little something-something extra.

Or you could use one scale/mode for the ii-V part and another for the i7 part. I just think it's a mistake to act as if those three chords have no relation to each other or don't inhabit the same basic harmonic space, because I don't see how you can make them make sense that way.

Just my $0.02.

[Richard Lindsey]

Originally Posted by Bryan R. Tyler

One thing that confuses me about that is that if a D half-diminshed fit into the same key, then wouldn't it have to ("have to" is obviously a loose definition in jazz I'm coming to find ) represent the 7th step and)the Cm have to represent the 6th step (Aeolean)?

I'm afraid I don't know what you mean by the 7th and 6th step here, Bryan.

[Bryan R. Tyler]

Originally Posted by Richard Lindsey

And a D half diminished can easily be built from Cm. It is in fact the prototypical ii7 chord in Cm; there's no note in it that doesn't exist in Cm. You can build it from either C aeolian or C harmonic minor. And a G7 alt is just a G7 with some 1000 Islands dressing on top. Again, if you wanted, you could think of that whole little harmonic space as a kind of C harmonic minor, with a little something-something extra.

So if I see a D half diminshed chord written out, should I not assume it's the 7th step of the key? It's probably because I'm not used to reading jazz charts, but I usually think 5th when I spot a V7 chord or 7th when I spot a half-diminished chord.

And the confusing part seems to be that the Cm was specifically written out with a Dorian scale rather than Aeolean, which has several notes that are not in the D Locrian scale.

[Bryan R. Tyler]

Originally Posted by Richard Lindsey

I'm afraid I don't know what you mean by the 7th and 6th step here, Bryan.

Sorry, I worded it badly. If the key is Cm and the second degree is a D half diminished, I would normally assume the Cm is an Aeolean.

[Richard Lindsey]

Originally Posted by Bryan R. Tyler

So if I see a D half diminshed chord written out, should I not assume it's the 7th step of the key? It's probably because I'm not used to reading jazz charts, but I usually think 5th when I spot a V7 chord or 7th when I spot a half-diminished chord.

And the confusing part seems to be that the Cm was specifically written out with a Dorian scale rather than Aeolean, which has several notes that are not in the D Locrian scale.

Well, in Cm, any chord built on D can't be the 7th degree of the scale, by definition. It has to be the 2nd degree. If the key is C, D is the 2nd, not the 7th.

It's not uncommon for the "flavor" of the tonality to move around a little at various parts of the tune. To play a C dorian over the i gives one flavor; to use the Dm7b5 at the turnaround gives a different one.

[Richard Lindsey]

Originally Posted by Bryan R. Tyler

I'm assuming the C7+9 is there for tension that's resolved with the Fm, correct?

You can think of the C7+9 as a secondary dominant--the V7 of the iv.

[arcellus]

richard made some good points in that last longer post. and playing one scale, making the necessary alterations on the fly, is a great way to practice playing changes. that's really what we want to do when we improvise anyway - create one cohesive melodic statement using the colors implied by the chords as guide posts.

another great book that helped me a lot - in particular, employing the melodic minor scale modes - is "the jazz theory book" by mark levine. it's big, heavy and expensive - but worth every penny.

[Richard Lindsey]

Originally Posted by arcellus

another great book that helped me a lot - in particular, employing the melodic minor scale modes - is "the jazz theory book" by mark levine. it's big, heavy and expensive - but worth every penny.

I've not delved into that one very much, but by all accounts it's a superb resource.

[HaVIC5]

Also keep in mind that there are a lot of other scales you can use on an altered-dominant chord: H/W Diminished, Whole Tone, 5th mode of Harmonic Minor. The "+9" just indicates that the chord is altered - exactly how it's altered is up to you.

While there is some pick and choosing with regards to altered dominants, its not quite as clear cut as seeing the #9 and going hogwild with dominant-type scales. #9 technically only implies the use of b9, NOT all of the altered dominant tensions (b9, #9, b5 (#11), and #5 (b13)) Granted, it won't make much difference in a performance situation between an altered scale and a mixolydian b9 b13, but the latter will sound more coherant with the changes.

Oh yes, and you really wouldnt ever use a whole tone scale with an altered dominant. The natural 9 clashes like crazy with the harmony. Save whole tone scales for #5 dominants.

[arcellus]

Originally Posted by HaVIC5

Oh yes, and you really wouldnt ever use a whole tone scale with an altered dominant. The natural 9 clashes like crazy with the harmony. Save whole tone scales for #5 dominants.

Good point.

[Bryan R. Tyler]

Originally Posted by Richard Lindsey

Well, in Cm, any chord built on D can't be the 7th degree of the scale, by definition. It has to be the 2nd degree. If the key is C, D is the 2nd, not the 7th.

Sorry- I'm still auto-associating with major keys (locrian=7th, etc.). But my point was that in my inexperience seeing the D Locrian would make me assume that C was Aeolean despite being written out as Dorian. Should I always use the melody to guide what notes I choose, as an example like this shows that using the written chords alone might lead to some dissonant notes?

[Bryan R. Tyler]

Originally Posted by arcellus

another great book that helped me a lot - in particular, employing the melodic minor scale modes - is "the jazz theory book" by mark levine. it's big, heavy and expensive - but worth every penny.

I've owned that one for a while- read what I could but haven't read too much of the samples as my bass clef reading is abhorrid and treble clef is non-existant. That book should come with a 10 CD companion book or something- he references a lick from a song every paragraph