In this lesson, I'll demonstrate how to use upper structure triads to create melodic figures. By "upper structure triad" I mean any triad derived from the chord-scale, other than the 1-3-5 triad of the chord in question.
For example, let's look at the Cmin7 chord at the beginning of "Blue Bossa." The tune is in C minor, so the chord-scale for this chord is C natural minor, which is the same as E-flat major, so, theoretically, we can use any triad derived from the E-flat scale over this chord. Those triads are: E-flat major, F minor, G minor, A-flat major, B-flat major, C minor, D diminished. In this example, I'll just use the C minor triad, and one "upper structure triad," the B-flat major triad. Notice that the B-flat triad contains the b7 9 and 11 of C minor.
To get started, we'll lay out some B-flat major and C minor triad on strings 2, 3, and 4. We could use any voicings for these triads, and any sets of strings, but I choose these voicings and this set of strings for simplicity.
To establish the chord sound, I'll start my melody with the notes of the C minor triad. Then I'll move back and forth between C minor and B-flat major triads, ending on a C minor triad.
In the recording for this example, I've given the bass the root and fifth of the C-7 chord, though a C pedal would work just as well. To establish the the C-7 chord quality, I have the vibes playing the third and seventh of the C-7 chord.
To create coherence in my melody, I've used a few basic compositional techniques. I start with a motif on the C minor triad. This motif has two important characteristics, rhythm and shape, that I will develop throughout these two short phrases. The rhythm of the first B-flat major triad can be thought of an an augmentation of the opening rhythm: the eight note is augmented to become a quarter note. I repeat that rhythm on the C minor triad in measure two. So far I've gone down one triad, up the next, down the next. This sets up the expectation of going down the next, so, to create a sense of forward movement, I vary the pattern in measure 4. In measures five through eight, notice the stepwise movements from F to E-flat, E-flat to D, and D to C. These, too, create coherence, creating a kind of compound line.
When I analyze in this way, students often ask me, "Where you thinking about all this when you improvised that line?" No. During improvising, things are happening too fast for conscious thought. But I've spent enough years writing compositions, studying the compositions of others, doing counterpoint exercises, and trying different techniques in my practice sessions, that these things happen subconsciously.
I encourage you to experiment with creating melodic figures using upper structure triads. If at first you find it difficult to come up with good melodic figures, try writing out a simple motif and composting some simple variations. Play what you've written, and then use that as a jumping off point for improvisation.