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Understanding music to improvise better: form in jazz standards

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Jazz standards tend to consist of repetitive harmonic patterns and sequences. It is important to understand how these chord patterns are organised and the structure of the pieces as a whole. This will allow you to play in a more relaxed, and consequently more creative, way. In this lesson we will therefore discuss form and structure in jazz standards.

The importance of form: the 32-measure chorus

Improvising on a jazz piece is not just about playing by ear and instinctively, it requires a deep understanding of chords. You need to know the harmonic progressions and understand how each piece is structured in itself.

Jazz tunes tend to have a very repetitive structure, the most typical being 32 measures, divided into sections of 8 measures each. The performance of all 32 measures is called a chorus and normally each soloist improvises on one or more whole choruses, before giving way to the next soloist.

For example, in a quintet formed by a trumpet, saxophone, piano, bass and drums, the most frequent development of the piece will be:

  • 1st chorus, theme played by the two wind instruments together
  • 2nd chorus, trumpet solo
  • 3° chorus, sax solo
  • 4th chorus, piano solo
  • 5th chorus, repetition of the theme by the two wind instruments

Each instrument can play more than one improvisation chorus, but usually the 32 measures are indivisible, each soloist playing them in full at least once. An exception to this are very slow pieces (called ballads) in which sometimes the soloist improvises only on one part of the chorus, usually half of it, to avoid making the piece too long.

Sometimes it also happens that a soloist duets with the drums, playing 4 solo measures and then leaving as many to the drums, until the conclusion of the chorus. In this case we talk about "exchanges" with the drums.

This very orderly and symmetrical organisation helps the improviser not to get lost, even on an instinctive level it is easy to recognise the 8-measure sections and to know when the piece has come to an end.

Within these 32 measures there are also typical forms, precise patterns that organise the material both melodically and harmonically. So let's see which are the most common forms in jazz standards.

Different types of 32-measure chorus

The most common form in jazz standards is AABA. The piece begins with a clear section of 8 measures which we call [A], this section is repeated a first time, then there is a different section which we call [B], after which the initial part [A] is repeated, to complete the 32 measures.

A classic example of this type of form is the song that Duke Ellington's orchestra used as its opening theme: Take the A Train. This is the score of the whole chorus.

Take-the-A-train-Billy--AABA form
Take the A Train has the classic AABA form

Within the piece we have indicated the sections [A] and [B], we observe that they are organised in the AABA form. The AABA form is among the easiest to learn, because the entire piece of 32 measures can be reduced to just two sections, [A] and [B], of eight measures each.

However, this type of structure also has its drawbacks: you may lose track of the [A] sections and no longer know when to play the [B] part. In fact, since the chorus is repeated many times, the sequence will look like this:


As a result, you will be playing three [A] sections in a row, one concluding the previous round and two forming part of the new chorus. In order not to get lost, it is a good idea to distinguish these three similar sections: after the [B] part, there follows an [A] part that concludes the chorus, which then starts again with two [A] sections.

As well as Take the A Train many other jazz songs have an AABA form. For example: Satin Doll, Blue Moon, There is No Greater Love, Lover Man.

Another typical form of jazz standard is ABAC, where section [A] is repeated twice, but alternated with two different sections, [B] and [C]. Some examples of ABAC structure are: All Of Me, Fly Me To The Moon, But Not For Me, How High the Moon.

Other similar but less used structures are AABC, which we find in Autumn Leaves, or ABCA, such as Canteloupe Island. We note that all these forms are always quadripartite, and with a standard duration of 32 measures.

The majority of jazz standards therefore use a form of 32 measures, divided into sections of eight. Let's now take a look at somewhat less common, but still widely used, forms of jazz standards.

Form of 16, 36 and 40 measures

We have seen that the 32-measure chorus is undoubtedly the most typical and most widely used. It can happen that during a jazz concert, only pieces with a 32-measure chorus are played, with the exception of the blues (see below). However, there are some alternatives or variations.

Some pieces are built on a shorter chord progression of 16 measures. Two classic examples of 16-measure pieces are Summertime by George Gershwin and Lady Bird by Tadd Dameron. If we wanted, we could divide these pieces into sections of 4 measures. By doing so, within Summertime we recognise an ABAC form where each section consists of 4 measures instead of 8.

Summertime has an AABA form, with sections of 4 measures each

Lady Bird on the other hand has a structure without repetitions, the 16 measures of the piece are all different, although we recognise a similar pattern in the groups of 4 or 8 measures.

Questa immagine ha l'attributo alt vuoto; il nome del file è Tadd-Dameron-Lady-Bird-STANDARD-16-misure.png
Lady Bird has a chorus of 16 measures, without repetitions within it

There are also pieces that expand the 32-measure scheme to 36 or 40, however without changing the internal scheme. For example, East of the Sun has a chorus of 36 measures, with a form ABAC where section [C] lasts 12 measures instead of 8. The standard bossanova Garota de Ipanema has an AABA form with section [B] lasting 16 measures, and therefore has a chorus of 40 measures in total.

Other typical forms in jazz standards

A lesson on the form of jazz standards cannot omit mentioning two of the most frequently used structures: the Blues and the Rhythm Changes.

The blues is a musical genre with a rich and varied tradition. However, when we speak of "blues" in jazz, we are referring to a very specific type of blues: the 12-measure strophic form. These twelve measures are divided into three sections of four measures, the first of which insists on the tonic chord, the second on the subdominant chord and the third and last on the dominant chord

Starting from this relatively simple formula, jazz musicians have built more and more elaborate blues progressions. However, all of them are always classified within the same framework. Here is an example of a particularly elaborate and chord-filled blues, the famous Blues For Alice by Charlie Parker.

Blues-For-Alice-Charlie-Parker-BLUES 12 misure
Blues For Alice is a very elaborate piece, but it is still a 12-measure blues.

A jazz musician spends many years studying the blues in its most diverse forms, from the archaic blues consisting of only three chords, to the more sophisticated blues of Charlie Parker or other modern musicians. However, in the jazz repertoire the blues almost always has a 12-measure verse, so from the point of view of its form it is quite repetitive.

Something similar happens with the Rhythm Changes, a musical form that follows the AABA structure and is derived from the song I Got Rhythm by George Gershwin. On the harmonic progression of that song, hundreds of alternative melodies have been built, creating a whole sub-genre.

A bit like in the blues, the form is always the same, in this case AABA, but the chords within can be very different.

Final remarks: jazz is not only improvisation

In summary, the most commonly used forms in jazz are the 32-measure chorus, AABA or ABAC, the 16-measure blues and the Rhythm Changes. These repetitive and predictable structures are ideal for improvising, as the performer can concentrate on his creativity, not having to count measures in order not to get lost.

However, not all jazz is merely based on improvisation. Older musical forms, for example those of 1920s jazz, orchestral jazz and more modern jazz, often have much more elaborate structures. A composer who wrote very formally articulated pieces was for example Jelly Roll Morton, one of the fathers of jazz music.

Duke Ellington's works were also often very elaborate and did not just repeat the typical 32-measure chorus. However, if you are a jazz fan and want to play with other musicians, it is essential to learn the most typical choruses in depth, especially those of 12, 16 and 32 measures.

I hope this lesson has been of help to you, if you want to ask me questions about the most typical form of jazz standards, or simply leave your opinion about this article, you can write below in the comments. Thanks, talk to you soon!

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