Upper structure


In jazz music, the term upper structure or upper structure triad refers to a voicing approach developed by jazz pianists and arrangers defined by the sounding of a major or minor triad in the uppermost pitches of a more complex harmony.

Examples

Example 1: Below, a common voicing used by jazz pianists is given for the chord C79.
In the lower stave the notes E and B are given. These form a tritone which defines the dominant sound, and are the major 3rd and minor 7th of the C79 chord.
In the upper stave the notes E, G, and B are given together: these form an E major triad.
This E major triad is what would be called the upper structure. Considered in relation to the root C, the notes of this E major triad function, respectively, as the sharpened ninth, fifth, and seventh in relation to that root.
Example 2: The following example illustrates the notes of an F minor triad functioning as part of a C13911 chord :
In relation to the root of C, the C functions as the minor 9th, the F as the augmented 11th, and the A as the major 13th, respectively.

Application

Determining which additional pitches can be juxtaposed with the chord is achieved by considering the relationship between a particular chord and the scale it implies. An example follows:
  1. The chord C13911 contains the following notes, from the root upwards: C, E, G, B, D, F, A;
  2. The following octatonic scale contains all of these pitches, and fits/matches up with the C13911 chord: C–D–D–E–F–G–A–B–C; these scale elements form a pool from which melodic and harmonic devices might be devised.

    Shorthand notation

Common jazz parlance refers to upper structures by way of the interval between the root of the bottom chord and the root of the triad juxtaposed above it. For instance, in example one above the triad of E major is a minor 3rd away from C. Thus, this upper structure can be called upper structure flat three, or USIII for short.
Example two is called upper structure sharp four minor, and can be written shorthand as USiv.
Other possible upper structures are: