diminished colors / Two chord harmony

Folk, country and rockers take note, your are entering into a blues and jazz harmonic zone. Ever hear the term "half diminished?" Perhaps "minor seven flat five?" Maybe see the chord symbol, C min 7 b5 or C Ø or C Ø 7? Are any of these terms and symbols familiar to you? Yes? If no, well, let's hip you to the changes. All of these musical expressions or symbols above imply the exact same chord. Really? No doubt. Compare the following chordal colors. Example 1.

As we gradually diminish or reduce the size of the intervals between the pitches within each successive chord type as notated above, we are also aurally gradually decreasing the tonal stability in each successive chord.  We see a tonic type major seventh chord on the far left, a paragon of stability within the major tonality, and on the far right, the fully diminished seventh chord, the quintessential incarnate of dominant instability. Cool with this idea of a gradually reducing tonal stability, based on a gradual diminishing of the intervals within the chords? These five different chord colors in example 1 above are the basic harmonic components for creating the sensations of tonal gravity. The chord that fits the description implied in the title of this page is the C minor 7 b5, or C Ø, or the "half diminished" chord, one chord to the west before falling of the edge of the known tonal world. Here is a chart spelling out the pitches used to create the above chords. Example 1a.

The only diminished coloring that we commonly apply to the Two chord type is to simply "diminish" the perfect fifth interval by half step. Compare the following minor chord colors. Example 1b.

Hear the difference? The chords are voiced with the alternating fifths in the lead. So, from within the equal tempered system, how can we organically create this half diminished color? Well, simply from the major / relative minor scale. Building the natural minor scale from the pitch C, the relative minor of Eb major, we can locate the half diminished chord color from the second scale degree. Here is a chart spelling out the pitches. Example 2.

Easy enough eh? Cool with spelling chords? Can you see the three flats of the key signature of Eb major? Dynamite. Let's place this chord color into the Two / Five / One chord progression and dig the emotional environment it creates. Example 2a.

Are the pitches of the G 7b9 chord diatonic to C natural minor? Nope. We had to "borrow" a leading tone from the harmonic minor or melodic minor colors. Cool with this borrowing idea? American musicians of all the styles do it all the time. This above combination of ii min 7 b5 and V 7 b9 from example 2a is quite common in the literature. Why? Well, the b5 of Two and b9 of Five are the same pitch? Check out the Rogers and Hart classic ballad titled "My Funny Valentine."

Speaking of common practice, using this Two / Five coloring to cruise into the major tonal environment is quite common in the jazz realm of things. Example 2b.

We oftentimes hear this tonal "surprise" in standards. Cole Porter's contribution "I Love You" employs this somewhat "deceptive" cadential motion. 

Even leaving out the Five chord, the motion from Two half diminished to a tonic One chord in the major tonality can yield some gorgeous results. Example 2c.

Kind of a V 7 sus 4 b9 thing eh? No root, 2nd inversion maybe? Either way, nice motion huh? Another perhaps more modern motion with the half diminished color is to move by half step down into the major tonality. Example 2d.

Got a sense of applying the diminished color to the chord built on the second scale degree, the Two chord? So where can we place this half diminished color in the music? How about examining the diminished colors in either the major or minor tonalities?

"Even after a bad harvest, there must be sowing." Seneca