…from major to minor.
I sometimes get “Dear Auntie Jase” emails, and I think it can be useful to post the results of the correspondence (anonymity guaranteed of course). If you have any questions, do contact me and I’ll try to help more than confuse.
So you’ve learned your II V I stuff in the major keys. You’ve figured out that (unless you’re choosing alterations), the chord-scales all come from the same parent scale, you just have to be a bit careful with some tones over some chords.
You move on to do the minor II V Is. All of a sudden, things get far more complicated and you find that people play combinations of different scales. What’s worse, they argue about what is “right”…
So which scales to choose over a minor II V I? Well, there’s no real right or wrong here, it really is rather a matter of taste. Experienced players mix and match the different choices. We’ll have a look at the possibilities (egs given for a II-V-I in C minor).
II CHORD – D HALF-DIMINISHED
D Eb F G Ab Bb C (7th mode of Eb major)
The problem here is that the Eb sounds dissonant (against the root) if you play it on a strong beat. If you play through it, it’s fine. A lot of bebop-era players work this way. One thing you can do is be careful where you place the Eb (or just avoid it), but another solution is to simply raise the Eb to E. Which gives you the same as…
6th mode of Melodic Minor:
D E F G Ab Bb C (from F melodic minor)
A lot of post-bop players work this way.
In general, you’ll find that even the very advanced scale-based players stick very closely to just the chord tones on a half-diminished chord. Those tones do their job perfectly and prepare you for…
V CHORD – G7 ER SOMETHING
Slightly different thinking here. While you often alter a dominant in a major cadence, there is at least one agreed basic unaltered starting point. Not really the case in minor cadences.
The two most common chord sounds used over the V in a minor II-V-I are 7b9 and 7alt. So your first choices are either of:
Half-step whole-step diminished scale:
G Ab A# B C# D E F
G Ab A# B C# D# F (this is the 7th mode of Ab Melodic Minor)
It’s not an exact division, but generally, the sound of 7b9 belongs more to swing and early bebop, and 7alt to post-bop. Again, it’s a case of mix and match, but as a very rough guide, 7b9 sounds “Birdy” and 7alt sounds “Traney”.
You can also play the G whole-tone scale – I tend to think of it sort of like the hick relative of the more urbane alt… But this country cousin knows some tricks – whole-tone can be used much more flexibly than you often hear (see Monky Business).
I CHORD – C MINOR (BUT WHICH?)
Aeolian (natural minor, aka classical melodic minor descending):
C D Eb F G Ab Bb
IMO this is an example of classically trained musicians applying theory without actually having listened to much jazz. You rarely hear Aeolian played by an actual jazz musician.
C D Eb F G Ab B
Another borrowing from classical theory. It is used sometimes, but that augmented 2nd between Ab and B can sound a bit “ethnic”… We’ll return to harmonic minor below.
C D Eb F G A Bb (2nd mode of Bb Major)
This one is definitely used, and quite a lot in hard bop, basically because the natural 6th makes it sound “tonicy” but the b7th gives it a bluesy character (hard bop was a reaction to bebop and largely about making jazz sound more down-home). You’ll often see charts with the I minor chord written as Cm7 – this may be an instruction to use the Dorian, and it’s often in the process of going somewhere else, but it’s just as often a convention some people use when they really could have just written Cm.
Melodic Minor (aka classical melodic minor ascending:
C D Eb F G A B
More of a modern post-bop sound.
Considering all four possibilities together, you can see that the only point of argument is exactly what to do with the 6th and 7th scale degrees (classical theorists had the same problem). But it really ultimately is a matter of taste.
MINOR II-V-I AS A WHOLE
You can play C harmonic minor over the whole lot.
This has the advantage of being a single scale that contains all the necessary chord tones for all three chords. A lot of people start out with it, because it seems like the best equivalent of the major scale for playing all three chords of the cadence. However, it has the disadvantage of having omissions and weaknesses on all three chords.
Crucially, it has that augmented second between the flat 6th and major 7th of the key, which is strictly speaking a scale step but also sounds like an interval of a minor 3rd. Now jazz musicians certainly do fluently combine scale steps and intervals when soloing. But constant over-reliance on this sound can make you sound a bit like a furry-hatted Cossack or an Andalucian troubadour… If that’s the sound you’re going for, fine, but there are other ways of playing on all three chords.
It is a decent fallback position though, especially when the chords are whizzing past at high velocity.
To sum up, whereas in a major II V I alterations are optional, in a minor II V I they’re desirable, perhaps even necessary. There isn’t one simple option, but look on the bright side – you get loads of choice for your trouble.
As ever – let me know what you think.