The most basic four-note voicing for a seventh chord is the seventh chord itself, demonstrated below for the II-V-I in the key of C:
However typically in a jazz setting, voicings are played rootlessly to avoid redundancy when a bassist is present. Instead of playing the root of a chord, one can play the 9th instead:
Notice that if we hold on to the 9th of the II chord and let it carry over, it becomes the 13th of the V chord. This is a common way to voice II-V-I’s, allowing an elegant transition between the II and the V chords by simply lowering one note:
To take it one step further, one may also omit the 5ths completely and only use 9ths and 13ths to complement the basic two-note voicings made up of 3rds and the 7ths for all chords:
Practice four-note voicings in all keys descending by tones as shown below. In order to go through all 12 keys, descend following the two complementary whole tone scales. Try different inversions to find out which inversions work for which keys:
Next try to play the four-note voicings on the individual chords outside of II-V-I’s. For example, play II chords in all keys following the cycle of fourths, then do the same for V and I chords. To make the chord transitions smooth, try different inversions going from one chord to the next.
The same four-note voicing concept can be applied to minor II-V-I’s with some small differences. In a major key context, the chords of a II-V-I are basically the second, fifth and first modes respectively from the same major scale. However in a minor key context, the three chords are not necessarily derived from one single scale. Instead it is better if the three chords are examined separately:
- The half diminished chord can be considered as built from the second mode (Locrian #6) of the harmonic minor scale, the seventh mode (Locrian) of the major scale, the sixth mode (Locrian #2) of the melodic minor scale, or the half-whole diminished scale.
- The V chord in its most basic form is just a dominant seventh b9 chord and can be considered as built from the fifth mode (Phrygian dominant) of the harmonic minor scale. We can also highlight the 13th of the chord and consider it as built from the half-whole diminished scale, or make it a V altered chord and consider it as built from the seventh mode (Super Locrian) of the melodic minor scale.
- The I chord could be derived from the harmonic minor scale, the melodic minor scale, or the second mode (Dorian) of the major scale.
The voicing for each chord may slightly vary depending on which harmony the musician chooses to use. For instance, the II chord would contain a flat ninth if diminished harmony (Locrian) is used, but would contain a natural ninth if melodic minor harmony (Locrian #2) is used. Most of the time a flat ninth on a half-diminished chord is treated as a passing tone because of a some dissonant quality, and the use of melodic minor harmony with a natural ninth is much more common in jazz. One may also create voicings that are compatible with both types of harmony by avoiding the ninth in the chord.
From the half-diminished chord, we can simply lower the seventh by a semitone and carry it over to the third to get various voicings for the V chord:
Finally for the I chord:
Which harmony to use over a minor II-V-I depends on the context of the tune, as well as the taste of the musician. In jazz it is most common to use melodic minor harmony for all three chords: Locrian #2 (6th mode) for the II chord, Super Locrian (7th mode) for the V chord, and melodic minor (1st mode) for the I chord. Each chord therefore is considered as derived from a different melodic scale. Using the key of C minor as an example, the three melodic scales are F melodic minor, Ab melodic minor and C melodic minor respectively. With this in mind, another approach to voicing a minor II-V-I is to simply transpose the same voicing shape into each melodic minor scale. The shape should highlight the tritone that is present in the V chord. One commonly used shape is illustrated below:
In the I chord above an inversion of the voicing shape was used to make the transition smoother. Another neat thing to notice about this shape is that in the V chord it is also the four-note voicing for the tritone substituted dominant seventh chord due to the highlighting of the common tritone. This tritone substituted dominant seventh chord is now derived from the fourth mode (Lydian Dominant) of the melodic minor scale:
Practice minor II-V-I four-note voicings in all keys descending by tones as shown below. In order to go through all 12 keys, descend following the two complementary whole tone scales. Try different shapes and inversions to see what works well: