Modality and Freedom

What does it mean to embrace modality in improvisation, as opposed to tonality or atonality?

Modality is a fertile subject in jazz history. It was consciously and explicitly embraced by Miles Davis, John Coltrane, and many contemporaries. They used it to find new frameworks for improvising when they felt that following predetermined chord sequences based on popular songs had become a limitation (though they did not abandon these chord changes entirely, nor what they had learned.) Modal harmonic schemes gave musicians more freedom, both in terms of spontaneity and of the latitude to introduce larger, if undetermined, structures within the course of improvisation. Outside of the sphere of "music itself," new freedoms were being sought in at the highest level of the polity and national community. 

To move toward modality is to privilege the horizontal—the unfolding of music in time--over the vertical or harmonic as the key principle of musical organization. It spoke to the moment because "the people" relate instinctively to modality and its related effects. After all, modality broadly conceived is a common feature of most world music and of “folk” music. It is arguable that one of jazz’ most fertile tributaries, the blues, is modal, both in the sense of its pitch system and of emphasizing horizontal development. Blues musicians only have their story to tell. They’re just not that into harmony, or not in the sense derived from European art music of functional tonality.

To ask what it means to embrace modality is prompted by my interest in Pre-Baroque European art music, which was created within a modal system a thousand years in the making. (I thank Susan Boynton, the medievalist in Columbia University’s Music Department, for confirming these observations.) While there are of course differences, medieval and Renaissance composers viewed harmony as an artifact of melody, an incidental set of relationships produced by interwoven melodies in the distinctive polyphony of their era. In this music as well, then, interest is sustained and unity achieved by sequences of pitches with their own integrity, and not by their hierarchic relationship to a single governing pitch, as in the functional totality that Western ears became accustomed to due to the hegemony of Classical forms from the time of Haydn and Beethoven.

Functional tonality—the organization of harmonic and structural motion toward a governing pitch center—means more than just being in a certain key, with the exact set of pitches given by their position in relation to the key pitch. In classic functional tonality, the ear is guided toward that pitch center by elaborate mechanisms, bass movements like cycles of fifths and voice leading tones, to sense that key as final. That is a powerful way, perhaps a necessary one, to establish tonality in the strict sense. European art music only reached this point with Arcangelo Corelli; it was perfected by Classical composers; and then it broke down under repeated innovations that avoided, delayed, or confused that sense of cadence toward a governing pitch during the Romantic and early 20^th century eras. Jazz had appropriated this tonal edifice for its purpose of improvisation, via ragtime, Tin Pan Alley, and direct Classical influence, by the time Coltrane and Davis embarked on their life’s work.

In a modal system, one pitch may define a mode. It may be the first and last note to be sounded. It may be sounded more often than other notes. It may be sounded more or less continuously throughout a musical work, to the point of being a drone. But it is only first among equals. 

Without elaborate mechanisms to establish tonality, the note that gives its name to the mode is not conclusively the “key” – the vanishing point around which the picture is organized. Without the grid of functional tonal movement to guide the ear toward the tonic pitch, there is ambiguity as to what choices of or groupings of pitches, are most prominent in the handful the mode “permits.” And far from creating chaos, it is a productive ambiguity, capable of suggesting many directions but requiring none. Composers before Monteverdi who worked under the modal system knew this. And so did the jazz musicians who consciously brought modality back into improvisation during the 1950s. 

Thousands of modes have been “discovered,” and their properties parsed, across the many international musical forms that employ then. In this post, I am simply referring to the “Greek” modes commonly employed in jazz parlance and performance since George Russell began using them to describe jazz practices: Dorian, Mixolydian, Phrygian, and Ionian (the last to be distinguished from the “major key”). That said, the productive properties of modality hold as much for medieval and early Renaissance music as for jazz, at this broad theoretical level. 

The first note of a set (or scale) may designate the mode (E Phrygian; D Dorian, etc.) Other tones compete for prominence, however. The lowered seventh has a mysterious pull away from the nominal mode key, making itself a contender for final or governing pitch. Hence its ability to evoke latent or unseen power in religious music, such as chant, and in Latin American music and the blues. Vertical relationships are possible in pre-Baroque modality but no sequence must be followed. Without such preset harmonic underpinning, triadic combinations (very much used by time of the Renaissance) may still be freely chosen from the set of permissible notes in the mode. The D Dorian mode contains the “minor” triad D-F-A, but also the “major” G-B-A, rendering it ambivalent as to these two classic qualities, or at least opening the possibility of a sustained major passage. 

John Coltrane knew this and exploited it when he performed his famous modal composition “Impressions.” The song’s entire harmonic scheme consists of 8-bar sections of D Dorian and Eb Dorian (forming the A and B sections, respectively, of the classic AABA popular and jazz song form.). But he sometimes interpreted the mode as G Mixolydian (or G dominant 7^th) by playing riffs associated with it for long sections (but not necessarily for the exact duration of the 32-bar song structure). Fourth triads, such as D-G-C or A-D-G, both found in the simple Dorian mode, are not only available, they are natural artifacts of selecting this mode, due to their many compelling voice leading possibilities within it, just as major or minor triads are in the case of tonal harmony. (See Susan McClary, “Modal Subjectivities: Self-Fashioning in the Italian Madrigal,” especially the chapter “I Modi.”) 

The bi- and polytonality developed by Miles Davis, Wayne Shorter and Herbie Hancock throughout the 1960s and beyond depended on their experience with this ambivalence, or equivalence, of alternating vertical pitch sets in the first wave of modal experimentation during the late 50s and beginning of the 60s. Those versed in jazz argot may recall “slash chords” which superimpose two triads or chords with non-chord bass notes. This manner of interpreting chord sequences, now quite conventional in jazz, is at the root a more sophisticated way of handling the ambiguity of underlying modes for each chordal scale and exploiting the possibilities of unexpected common tones, and suspended cadence they offer that were first developed at the time of “Kind of Blue” and “Impressions.”

In modality, structure can be generated at the improvisers’ will. One can pick a melodic cell—a handful of notes permitted in the mode—and repeat it or stress it without regard for some changing bass line or chord structure underneath, as Coltrane constantly does in Impressions. Insistent repetition of one “riff” or melodic groove is a device that funk and blues musicians know well: just stating a melodic figure, even a simple one, creates a hypnotic effect that fuels the groove and provides opportunity for dramatic release. These ad hoc or arbitrary melodic figures may also suggest a harmonic region as well as rhythmic pattern—they are constitutive of melody. In either case, the other musicians in the group may easily perceive that direction and go with it—or choose not to, but either way the openness becomes productive of improvisational artifacts. The soloist, perhaps pushed or pulled by the group, is free to develop these ideas over many measures, sometimes longer than the 32-bar parameter natural to conventional song-form improvisation.

These large structures generated in modal improvisation are open structures. The soloist may decide how much time will be spent in a certain region or melodic/rhythmic groove. It is true that in adhering to one mode, one accepts the risk that it will be monotonous, as a drone is by definition. The level of interest depends on the skill of the improviser to forge singular events, out of rhythm, pitch sequence, timbre, sheer unadulterated surprise (shrieks for example). Having a compelling rhythm—an expressive statement about time, not just executed in time—becomes paramount. The unfolding of an artistic statement in time, the drama of surprise, accident, emergent structure, perhaps ecstatically generated singularities are all at a premium in free or open form jazz, which dispensed with tonal centers of modality altogether, but which the latter thus logically anticipated.

Before the trend toward modal jazz in the late ‘50s, the sense of drama, surprise and suggestive ambiguity were all exploited masterfully by Lester Young (Coleman Hawkins’ and Don Byas’ sense of structure, while masterful, was more architectural and even physical, building to an athletic climax.) And Young often dwelled on or ended phrases on the sixth and ninth tones, avoiding the main triadic tones without grating dissonance. In other words, he used ambiguity—and like many musicians deeply versed in the blues, suggested attributes of modality.

Where is the gold, in artistic expression, but in exploring ambiguities that create new meanings?