The great thing about modern jazz harmony is that there are seemingly endless possibilities for organizing tonal material. Here’s a melodic line that I discovered as I was improvising over V7-I cycles, while exploring the relationships between two different 7th chord tonalities. Take a look at the sample below:
Here I’ve combined a C# Minor (Major 7) and a Bb Major 7 over a G7 chord. If we look at the tensions of each chord as they relate to the G7, we get +11 (C#), 13 (E), 11 (B#, or C), -9 (G#, or Ab) 9 (A), +9 (Bb or A#), 5 (D) and 7 (F). Lots of tension. But it is the way these two arpeggiated chords work together that creates this unusual sonic relationship. They are a minor third apart (or major 6th, depending on where you start, and taking into account the enharmonic labelling I’ve used) with different color qualities. I’ve connected the chords via voice leading (which is why I think the line sounded so melodic to me when I discovered it) and resolve the pattern to the +11 of the tonic (C Major), finally ending the line on the 9th of that chord. This is a very dense, “modernistic” sounding melodic line that makes a strong statement. Play it in all twelve keys (I’ve written it out) to give your ear a chance to absorb these tensions. (Click below for the pdf. I’ve also included a midi version to listen to.) If you like this etude and wish to explore more with symmetrically related tonalities as they apply to Dominant 7th chords, take a look at my books, Diminished Scale Diatonic Triad Pairs and Augmented Scale Diatonic Triad Pairs.