Theme

• Blues Form
• Song Form
• Other Forms
• Melody and Harmony

This is a preview of the educational program A Jazz Improvisation Almanac which is under development for the Outside Shore Music Online School. Feel free to browse this preview and learn what you can from it. For a more completed product, though, check out the original freely browsable jazz textbook, A Jazz Improvisation Primer.

Most jazz compositions contain a single primary theme that serves as the basis for further development and improvisation. A theme generally consists of a melody, often called the head, and its accompanying chord progression. The theme often follows one of several common forms or outlines, such as the blues blues form or song form, both of which are described below.

Blues Form

A theme that follows the blues form is usually twelve measures long. Originally, the blues was primarily a vocal music, and the traditional blues form contains three four-measure phrases that follow the pattern AAB. That is, the first phrase is repeated and then followed by another phrase that answers or contrasts with the first. For example:

The chord progression in a blues composition is traditionally anchored by three chords: the I chord, which harmonizes the first phrase, the IV chord, which harmonizes the second phrase, and the V chord, which harmonizes the third phrase. In the key of C, these chords are C, F, and G, respectively. There are actually many variations on the blues progression; these are described in more detail elsewhere. Another point to observe about the blues form as used in jazz is that the melody rarely follows the AAB pattern seen in traditional blues. The following is a typical jazz adaptation of a blues form:

Some jazz compositions that follow the blues form include "Billie's Bounce" and "Now's The Time" by Charlie Parker, "Straight, No Chaser" and "Blue Monk" by Thelonious Monk, "All Blues" and "Freddie The Freeloader" by Miles Davis, and "Mr. P.C." by John Coltrane. There are literally thousands of other examples.

Song Form

Another popular form for a theme in jazz is the song form. This form is 32 measures long, and is divided into 8 measure phrases that follow the pattern AABA. The first phrase is repeated and followed by a contrasting phrase called the bridge, which is then followed by another repetition of the first phrase. For example:

Note that the repetitions of the A-section are not necessarily exact; they may differ slightly in the last couple of measures. Often, as in the above example, the end of the first phrase is designed to lead back naturally to the beginning for the second repetition, whereas the end of the second phrase is designed to lead to the bridge, and the end of the final phrase is designed to conclude the song.

The bridge in an AABA form often introduces a temporary key change. But even if the bridge starts out in a different key than the A-section, it almost always manages to resolve back into the original key for the final A-section. The example above illustrates this point: the A sections are in Bb, but the bridge starts out with a ii-V-I progression in G minor that eventually returns to Bb.

Many songs performed by jazz musicians were popular songs of the first half of the 20th century that have been adapted to a jazz setting. These songs are referred to as standards. Most follow the AABA song form, although a few use other patterns such as ABAC or ABCA. Some examples of standards include "My Funny Valentine", "Body And Soul", and "As Time Goes By" (all AABA), and "When I Fall In Love" (ABAC).

Song forms are especially common in compositions written for musical theater by composers like George Gershwin, Cole Porter, and Richard Rodgers. Often, the theater performance of a song features a introduction, called a verse, that eases the transition from dialogue into the song itself:

Jazz musicians rarely perform the verses to songs, although vocalists are more likely to include them than instrumentalists.

While many of the song form compositions played by jazz musicians come from popular music or the theater, jazz composers write music with this form as well. Original jazz compositions with AABA song form include "Take The 'A' Train" by Duke Ellington, "Round Midnight" by Thelonious Monk, "So What" by Miles Davis, and "Lonely Woman" by Ornette Coleman.

Other Forms

In addition to blues and song forms, the themes to some compositions contain more complex patterns of phrases and repetitions; indeed some contain no discernable pattern at all. Certain standards, such as "Stella By Starlight" by Victor Young, fit this description:

Many compositions by jazz composers such as Horace Silver, Wayne Shorter, and Herbie Hancock use similarly complex forms for their themes:

Most compositions contain phrases with lengths of 4 or 8 bars, but some compositions, particularly ones with unusual forms, use other phrase lengths:

Compositions may contain multiple themes, often separated by improvised sections, or presented as suites of shorter pieces. Compositions such as these are sometimes referred to as long form compositions. While popular in classical music, these tend to be less common in jazz, perhaps because jazz musicians are usually more interested in improvisation than composition. Some example of long form jazz compositions can be found among the works of Duke Ellington, Charles Mingus, Randy Weston, Muhal Richard Abrams, Anthony Braxton, and Wynton Marsalis. The following example demonstrates the different themes in one long from composition. Here is an excerpt from the first theme:

Here is the second theme:

And here is the third theme:

Melody and Harmony

The melodies and harmonies in a theme in a jazz composition generally share the qualities described earlier. The melodies may involve fast runs, unusual intervals and syncopation, and they are often based on riffs and blues scales. The harmonies often involve complex chords, and they may be tonal, modal, or atonal.

In an AABA or similar form, it is not uncommon to leave the bridge open - that is, to compose no melody for it, but rather to improvise one during performance, usually based on a given chord progression. For example:

Another common device is to compose new melodies based on the chord progression to another tune. This type of composition is sometimes called a contrafact, although this term is rather obscure in the jazz world. One particular song, "I Got Rhythm" by George Gershwin, has become an especially popular model for jazz composers. Here is the original song:

And here is another composition based on that chord progression, which is often referred to as the "rhythm changes":

Since chord progressions are not covered by copyright law, this allows a musician to create an "original" composition, and thereby avoid paying royalties for performance or recording of that composition, while keeping a familiar chord progression to improvise over.

Some compositions may be more concerned with melody than with harmony. Many pieces by composers such as Ornette Coleman have relatively simple forms and melodies, but contain no predefined chord progressions. The following is an example of such a theme. Note there is bass accompaniment, but it is not playing any particular chords:

Copyright 2000 Outside Shore Music
Authored by Marc Sabatella

Theme