Jazz area of study: the features of jazz including swing rhythm, improvisation, the head-solos-head structure, extended and altered chords (sevenths, ninths), the walking bass and comping, blues influence, and the main styles, recognised in listening extracts.

What this dot point is asking

This is one of the optional areas of study in the WJEC Appraising exam. It asks you to recognise and describe the musical features and styles of jazz in listening extracts: swing rhythm, improvisation, the head-solos-head structure, the rich, extended harmony, the walking bass and comping, the blues influence, and the main jazz styles. You should hear and write about these using correct terms.

The answer

Rhythm: swing and the groove

Not all jazz swings (some is in a straight or Latin feel), but swing is the classic groove, and recognising it is central to identifying the style.

Structure: head, solos, head

Many jazz performances follow head-solos-head: the head (the main tune or theme) is stated, then soloists improvise over its chord changes (the harmonic framework), taking turns, before the head returns to close. Common frameworks are the 12-bar blues and the 32-bar AABA song form, repeated as a cycle (a chorus) under each solo.

Harmony: extended and altered chords

Improvisation and the rhythm section

Improvisation is the heart of jazz: over the chord changes, front-line instruments (such as trumpet or saxophone) invent melodies in real time, developing motifs and trading solos. The rhythm section both supports and reacts: piano or guitar comp (improvise chordal accompaniment), the double bass walks, and the drum kit keeps swing time and interacts with the soloist (sometimes "trading fours"). Call and response and collaborative spontaneity define the texture. Styles to recognise include early jazz and swing (big bands, swing feel), bebop (fast, virtuosic, complex harmony) and cool jazz (relaxed, smoother), among others.

Examples in context

Model paragraph (describing a jazz extract). A jazz extract usually reveals its style through groove, structure and harmony. It often opens with the head, the main tune stated by the front line over a swinging rhythm section, the walking bass striding through the chords, the ride cymbal lilting and the piano comping rich, extended chords behind. Once the head is done, the form repeats as a cycle and a soloist takes over, improvising fresh melodies over the same chord changes, the rhythm section reacting beneath, before another player takes a turn. The harmony is the giveaway of the idiom: sevenths and ninths, ii to V to I motion and blue notes colour everything, while the swing feel and syncopation drive it forward. Describing such an extract means naming the swing rhythm, the head-solos-head structure, the extended harmony, the walking bass and comping, and the improvisation.

Try this

Q1. What is a walking bass? [2 marks]

• Cue. A steady, mostly stepwise bass line, usually one note per beat, outlining the harmony.

Q2. What is the head-solos-head structure? [2 marks]

• Cue. The tune (head) is stated, players improvise solos over its chord changes, then the head returns.

Q3. Describe the main musical features of jazz, with reference to rhythm, structure, harmony and improvisation. [12 marks]

• What the marker wants. The swing rhythm and walking-bass groove, the head-solos-head structure over the 12-bar blues or 32-bar form, the extended and altered harmony with ii to V to I and blue notes, and the improvised solos supported by the rhythm section.