Music Lab

A Tuning the Air Journal

Saturday July 17, 2010 – Music Lab

More good work with voice leading. Not exactly the same players who have been working with this exercise for the past few weeks, but a definite sense of continuity and progress. With 5 players the last two week we managed a certain critical mass. If we can get everyone who has taken part in this series of exercises into the same room at the same time, things could get very interesting.

For the first hour we worked with diatonic triads in C Major, and then diatonic seventh chords in C Major. We began by walking up the scale, one player on the bass notes (roots to begin with, then roots and fifths, and eventually roots, fifths and thirds), the other players on assigned notes from the triad, first pulsing and later moving to circulating the arpeggios. We walked up the scale, once at the octave resetting back to the bottom and doing it again. Next we worked on how to move from the high arpeggio down as the harmony moved up. This required every player not only to know what note they were playing, but what interval within the chord of the moment it represented.

One of my hopes, if we can get enough players together, is to work through this exercise with two groups of circulators moving in contrary motion, chorale writing period of common practice style.

For the second half of the session we moved into an evolution of Rhythm Changes in the key of C. New bass player for this round. We began with circulating, but quickly reverted to pulsing chord voicings together in order to keep things moving. For this exercise, notes were not assigned, and it was up to the four players to find voicings together that were complete and convincing. We began with a simple…

I VI II V

…progression, getting the feel for how to find the simplest voice leading. The basic rules:

1. If your note is common to both chords, stay where you are.
2. If you must move, half steps are best, whole steps are good.
3. If absolutely necessary, moving a third is permissible.

The 4th rule, which did not figure much into this particular version of the exercise, since the chords where changing so quickly, is…

4. Moving a third or more within a particular chord is permitted if it helps to improve the voicing.

To this “pattern 1” we added a second pattern…

I I7 IV IVmin6

…creating the basic 8-bar “A” section of Rhythm Changes:

I VI II V
I VI II V
I I7 IV IVmin6
I VI II V

Or, in practical terms:

C Amin7 Dmin7 G7
C Amin7 Dmin7 G7
C C7 Fmaj7 Fmin6
C Amin7 Dmin7 G7

From here we moved into standard substitutions, gradually hipifying the chord progression. First, all of the Amin7s were replaced with A7s, as the V7 of II. After several steps we ended with this version:

I #Iº7 IImin7 #IIº7
IIImin7 ♭III7 IImin7 ♭II7
I I7 IVmaj7 IVmin6
I VI7 IImin7 V7

… in which the #Iº7 is functioning as V7 of II, the #IIº7 as V7 of III, the ♭III7 as V7 of II, and ♭II7 as V7 of I.

In C Major this is expressed as:

C C#º7 Dmin7 D#º7
Emin7 E♭7 Dmin7 D♭7
C C7 Fmaj7 Fmin6
C A7 Dmin7 G7

… in which the C#º7 is functioning as A7 (V7 of Dmin7), the D#º7 as B7 (V7 of Emin7), the E♭7 as A7 (V7 of Dmin7), and D♭7 as G7 (V7 of C).

We ran a little long, in order to hear this played in improvised circulation. Of course this is a pretty complex sequence of chords, and quite new to several of the players, so we inevitably settled into a few reliable paths through changes. With a little practice, a lot more dynamism would be possible. And with a few more players we could even develop improvised rhythm and melody parts.

Next week, perhaps the bridge? All kinds of potential fun awaits.