Lesson: Melodic 2-5-1 Mutation

In one of my earlier lessons I talked about using melodic minor scales to create different degrees of altered tension over functional dominant seventh chords. I got a request from a No Treble reader named Mark, asking for ii-V-I applications. Mark, this lesson is for you! We’re going to focus on different ways to reharmonize the ii-V-I and how that leads into altered chord and melodic minor applications.

Fair warning, this lesson gets a little heady harmonically. Also some of the concepts are more advanced and assumes you have some basic theory knowledge. My advice is to sit down with your bass (preferably at a keyboard or with a friend at a keyboard) and play through a lot of these examples and alterations.

The ultimate judge for any changes worth is your own ear. We can develop all kinds of theoretical explanations for using the melodic minor scale and reharmonizing songs until they’re barely a shadow of the original – but that is all just theory. I like to think that with practice your brain will transcend the information, so think of this as a spring board and something to ponder, not a strict set of rules. Everything changes in context and everything is subject to personal taste.

We’ll start off with a basic ii-V-I example and will transform it through the rest of the lesson:

D-7 | G7 | Cmaj7 |

First let’s analyze the available notes from each chord (focusing on the chord tones)

D-7 = D F A C
G7 = G B D F
Cmaj7 = C E G B

Those are all strong tones in each chord and could be used on any of the beats in the measure. The strongest beats in a 4/4 measure are 1 and 3, so combing a strong chord tone with a strong beat will really emphasize the harmonic structure in your solo.

The ii-V-I progression has a strong sense of resolution because of the inherent voice leading in the harmony. The voice leading occurs because the seventh of each chord resolves down a half step to become the third of the next chord. Here’s how that works: The seventh of the D-7 chord is C, it resolves to B which is the third of the G7 chord. The seventh of the G7 chord is F which resolves down a half step to the E which is the third of the Cmaj7. Additionally the roots of the ii-V-I progression also move counter clockwise around the circle of 5ths. This is meant to illustrate that the ii-V-I is a very cohesive progression and should be thought of as a unit.

This unit can be molded in different ways, there are multiple reharmonization options out there. Since Mark is focusing on the application of altered chords that’s where we’ll focus. One common reharmonization is to change the ii from a minor seventh to a half-diminished chord. The half diminished chord is the seventh mode in the major scale (locrian) and has the following structure:

D Eb F G Ab Bb C D

D F Ab C (root, flat 3, flat 5, flat 7)

The Ab in the D-half-diminished chord is the flat-9 for G7. Therefore reharmonizing the D-7 to D-7b5 means the G7 can be reharmonized to G7b9, an altered structure, to maintain continuity in the unit of the ii-V-I. The Cmaj7 could be reharmonized to a C-minor-major7 (C Eb G B) or left as Cmaj7, the resolution to either is fine and really depends on personal taste. As a caveat, do not do this reharmonization on the D-7 if the melody note over that chord is the A or B (5 or 6 of D-7) since both of those are flatted in the D-half-diminished scale structure. The G7b9 is close to being the second modal degree of the F melodic minor scale – the true form would be G7susb9. Therefore you can use a lot of the F melodic minor scale over this chord. This is the “down a whole step” approach outlined in the last melodic minor lesson on alterations.

Another reharmonization of ii is to make it a V chord – therefore a “V of V” structure. This works best in an isolated ii-V structure (without the resolution to the one). Therefore D-7 | G7 would become D7 | G7. So why would you do this? V chords are more easily altered and will give you a lot of flexibility in reharmonizing.

So now we have two V chords and you want to alter them. The most common alterations for a V chord are b9, alt, and #11, each of which has unique resolution characteristics. The V7b9 chords most often resolve down a 5th. They are derived from the half-whole diminished scale so we’ll note them because they’re common, but they are not as directly applicable to the melodic minor.

The V7alt and V7#11 on the other hand most definitely are! If you are not familiar with your melodic minor harmony the 7alt chord structure is the 7th mode of the melodic minor harmony. Therefore The D7alt would be the seventh modal chord derived from Eb melodic minor. Likewise the 7#11 is the fourth modal degree in the melodic minor chord. In Eb melodic minor that would be Ab7#11. Ready for the brain-breaker? The 7alt and 7#11 in the same melodic minor key are a tritone apart. Therefore, they have basically the same harmonic function and given that the melodic minor keys do not have any “avoid notes” they both resolve to the same chords. Think about that for a minute and review your theory on tritone substitutions (this lesson is complex enough!).

So where do each of these chords resolve? The strongest resolutions for a V7alt chord is

1. Down a 5th
2. Up a half step
3. Down a major third

Translated to with the tritone substitution to the V7#11 this would be

Both the D7alt and Ab7#11 are built from the Eb melodic minor scale so that will work in your improvisation. The first example (resolution to the Amaj7) does not have to be major, you can also resolve to the A-7 or the A7 smoothly, again it’s all up to personal taste. If you are going to reharmonize a V chord and the melody will be played make sure you check for clash-notes, otherwise the reharmonization will not sound good.

Now we have a couple different applications for the melodic minor scale in reference to a ii-V-I:

1. We can use them in different degree to control the tension over a functional domainant 7th chord depending on the level of alteration we choose to apply. This was outline in detail in my last lesson on melodic minor alterations.

2. We can use them after the reharmonization of a ii to the half-diminished form and the corresponding reharmonization of the V to the Vb9 with the “down a whole step” method from the previous lesson. This will give a very “outside” sound depending on how you play it. To stay “inside” use the melodic minor tones that correspond to a susb9 chord for the Vb9 (while thinking of it as the second modal harmony of the melodic minor form).

3. We can use them over reharmonizations to either V7alt or V7#11 which are tritones of each other. In each case the applicable melodic minor scale is a 4th down from the V7alt or a half step up from the V7#11. Each of these can resolve to three different chords, both major and minor, and the appropriate scale can be used in the resolution.

My recommendation is to experiment! Mark (and other interested readers) I hope this has given you something to chew on, the important thing to remember is that if you’re using the melodic minor form over a standard V7 (like the last melodic minor lesson) you will be creating different degrees of tension because your scale harmony will be different from the underlying chord harmony. With the substitutions and reharmonizations the melodic minor scales will be in harmonic agreement with the underlying chords and you will therefore be using the altered harmony and have a different type of sound (not as strong “outside” playing or tension). As I’ve said many times, the ultimate judge is your ear – if you like it run with it!

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Thanks Evan for this DEEP lesson! I will be spending some time going over all this. I usually will play the progression into my looper pedal quite slowly to give me time to expand my ideas on each chord. Now I have more fodder……Thanks again for the personal touch ;)Mark