two chord harmony

Two chord harmony ( ii min 7 ) in the major tonality oftentimes functions as a passing chord in the tension / release dynamic to the dominant, ( V 7 ), before resolving to the tonic ( I maj 7 ). In the case of a composition utilizing a minor key as it's tonal center, the following scale possibilities discussed below become choices for creating melodic ideas over the tonic minor chord, creating the various minor tonal environments. We converge to either or both of these creative environments in the musical ideas which follow as the colortones of the various groups seem to allow, imply and dictate.

Thinking C major as our tonal center, our Two chord is built upon D natural. Spelling the arpeggio, note the consistent cycle of minor 3rd major / major 3rd intervalic permutation in creating the minor 7th arpeggio. Example 1.

Using these core pitches from the arpeggio above, we begin to generate the following melodic possibilities providing different groups of pitches with which to create melodic ideas over Two minor 7th chords in the major tonality or tonic minor 7th chords in the minor tonality. Perhaps needless to say, the Two chord potentially lies within the domain of the dominant tension in the major tonality, thus it's pitches are also not only linkable to the dominant color but oftentimes players meld the two chords together, selecting a parent scale and applying it to both combined for creating their line of convergence, i.e., using D Dorian over D min 7 / G 7 etc.

Any of the permutations discussed previously that concern the interval studies, i.e. musical ideas built in 3rd's, 4th's, 5th's, 6th's, 7th's, 8th's (octaves), using the notes of the above D minor scales are applicable. So, basically the modal colors and a few twists. The following ideas are placed into the common Two / Five / One chord progression, creating paths of tonal convergence. Listed generally from tonal consonance ( inside ) to tonal dissonance ( outside ).

All of the pitches of the D minor pentatonic color can be viewed as being diatonic to the C major tonality yes?

Are the D minor pentatonic pitches diatonic to F major also? Yep. Major / minor right? Same group of pitches? Yep.

The pitches of the Dorian mode, when based on the root or fundamental D, the second scale degree of the C major scale, are all diatonic to the C major tonality. Hip to the modes?

And of equal importance, the Dorian mode also creates it's own ancient, minor tonal environment.

Using the tonic major scale / Ionian mode in convergence possibilities in the major tonality is perhaps the most consistently used group of pitches from which we create our melodic ideas over the last 500 years or so. Master of the obvious you say? Good!

The pitches of the Lydian mode, when based on the root or fundamental F, the fourth scale degree of the C major scale, are all diatonic to the C major tonality. The pitch F being the third of the D minor triad, the basis of the D minor 7 and the blue 7th of G 7, is often used as a passing tone to E, the third of the major triad of C major.

The pitches of the Mixolydian mode, when based on the root or fundamental G the fifth scale degree of the C major scale, are all diatonic to the C major tonality.

Adding the pitch G within the Two chord creates the cool minor 11 color.

These next ideas begin to introduce non-diatonic pitches into the convergence mix, note how the dominant chord begins to evolve towards the minor tonality.

Building the Aeolian color on D we encounter our first non-diatonic pitch in regards to tonal convergence on this page. Basically an F major scale, we oftentimes add the Bb ( V 7 #9 ) into the mix to add a bit of the blues color to our lines. Here we focus in on the half steps provided by the Aeolian group and emerge in a bluesy environment. Morphing diatonic major tonality towards the blues environment is very common in all the styles of American music, even if just for a bar or two. Emergence of it's character color in a song based in the major tonality oftentimes signals something in the thought process of the soloist. Signals what? To each their own interpretation I would presume. Try it, maybe as a last phrase / tag to one of your solos in the major tonality. R

The Aeolian mode is often considered as the base color of the minor tonality within equal temper, also known as the natural minor scale.

Building the Phrygian mode on the pitch D takes us towards some interesting non-diatonic possibilities. Look familiar? Right, the pitches of Bb major. Wouldn't that make C a Two chord type? Yep. And aren't the b3 and b7 blue notes? Yep. Using this color when moving towards the major tonality can create a bit of a surprise as the Eb moves up by half step to E, the major 3rd of the tonic major triad, as in bars 26 and 27 which follow. Adding in these blue notes to the dominant chord mix creates what is generically termed an altered dominant chord, here we alter the 9th to # 9 and augment the 5th to # 5.

This above idea is mostly a jazz / blues phenomena.

This next idea uses the color in perhaps a more common situation, moving diatonically to the minor tonality.

Sound a bit more correct? Both of the above convergence's are common in the literature, we find all sorts of surprises. Commonly the minor 3rd moves to major, it's a bluesy approach, major 3rd towards minor? Not nearly as common.

Building the Locrian mode on the pitch D we create the C natural minor / Eb major pairing of colors. Look familiar? Right the pitches of Eb major / C natural minor. Although rather non-diatonic, creating the impression of moving to the minor tonality then emerging in the major is cool and not uncommon in the jazz language.

And using this choice in the minor tonality, we are back into the diatonic realm of things.

More conventional yes?

The harmonic minor color presents some interesting ways to color the convergence in both the major and minor tonalities. Adding these non-diatonic pitches into the mix we create a cool dominant chord, the C# = Db yes, disguising our motion to the major tonality.

We can also use the C# as part of the Two chord creating the min / maj 7 configuration.

The melodic minor color adds a bit of the whole tone color to the dominant chord. Look familiar? Right, same pitches as G Lydian b7.

Other convergence ideas with the melodic minor color? Of course. Click here to go there.

Is there a more sure way to obscure tonal direction in our lines than by taking a more chromatic approach to one's lines? Mostly "peppered" into most of the American styles, using the chromatic color is one way that advanced jazz players get out and stay out. Here we simply chromatically enhance a diatonic idea.

Perhaps needless to say we can use the chromatic color to go anywhere, anytime, whatever, again the trick is to sound convincing. Thus, is creating convincing musical ideas simply based on our own ability to sing the line we want to play?

Into the minor tonality we go.

Cool with Two chord possibilities? Ready to place them within the tonal convergence chart?

Where to next?

review new ideas

"The difference between 'involvement' and 'commitment' is like an eggs-and-ham breakfast: the chicken was 'involved' - the pig was 'committed'." Unknown