This lesson refers to the keyboard reconstruction question (Q2. ABRSM Grade 8 Music Theory).
Phrases, Patterns and Sequences
The examiner will be looking for evidence that you have noticed patterns in the music, and that you can re-use those patterns effectively. Patterns can be just in the rhythm, or in the rhythm and the melody combined.
Phrase Structure
Try to get an idea of the overall phrase structure before you start writing anything. Phrases are most often written as balanced pairs, which often then build up into larger pairs, and often more weight/length is added to the end of a section, to help show that the section is coming to a close. Let’s look at this simple Tyrolian piece by a composer called Homan.
You can see straight away that the rhythm in bars 1-2 repeats in bars 3 to 4, and in bars 5 to 6.
Bars 1-2 make up the first phrase, which ends with an imperfect cadence, (remember, all phrases need to end with a cadence of some kind). This phrase itself is made up of two balanced sections – bar 1 contains one idea – the repeated chord, and bar 2 ends that idea. Phrases usually end on a reasonably long note too. Bar 1 ends on quavers (8th notes) but bar 2 ends on a crotchet (quarter note). This is the “questioning” phrase – it feels like it needs a response.
Bars 3 to 4 contain the “answering” phrase – we hear exactly the same musical idea, with the same rhythm and texture, but this phrase ends with a perfect cadence. So together, these two phrases make up an introductory larger musical statement which is complete in itself. We would now expect another statement of a similar length to answer these first 4 bars, so let’s look at what happens next.
Bars 5 to 6 are almost identical to bars 1 to 2 in the right hand – the only difference is the C#. But in the left hand, the harmony has changed completely – we now have chord vi, E minor, followed by A7, which is a clue that the music is going to modulate to the dominant, D major.
It would be possible to end this phrase off by using the same rhythm again, ending on a perfect cadence in D major, with a long end note in bar 8. But instead of adding two more bars, Homan actually adds four more bars. He also changes the melodic and rhythmic idea into something with slightly more momentum than used so far, and the end of each bar (bars 7-9) moves to a V7 chord. The effect is that we know the end must be coming, because the V7 chord sets up a need for resolution to the tonic, but the repetitive nature of bars 8 and 9 keep us hanging on, waiting for that moment to arrive, which of course it does, in bar 10.
This kind of structure, (three very similar blocks of material followed by a fourth which has an increase in tension), is very common. The increase in tension can be done in a number of ways. It can involve a livelier rhythm, faster chord changes, a change in articulation, extra bars, a different melodic shape, or any combination of these elements.
In this Dunhill piece for example, the first three phrases are built on descending scales in quavers (8th notes), swapped between the two hands. Bars 1 and 2 are identical to bars 3 and 4.
Bars 5 and 6 change the key of the scale, but are otherwise the same idea. Bars 7 and 8 change things significantly – the left hand becomes staccato, the shape of the melody is completely new, and the harmony changes much more quickly.
Bars 3 and 4 of the above piece are a repetition of bars 1 and 2, and bars 5 and 6 are a sequence of bars 1 to 2. It is a good idea to use plenty of sequences, imitation and repetition, because these techniques help “glue” a piece together, so that it makes sense to the listener.
It is very common that some of the gaps in the exam question will be places where imitation, repetition or sequences are the best thing to write, so if you find a place where an exact copy of previous material will work, go ahead and write it in!
In this example, taken from a piece called “Élégie” by Eduard Rohde, we could copy the right-hand part from bar 1 into bar 3:
Although the left hand is slightly different, the harmony is the same – it is G minor followed by C minor, so the melody will fit perfectly.
While it is advisable to repeat sections of music, do be very careful about repeating individual notes. Only use repeated notes in a melody if there is a good reason to do so, for example maintaining a particular rhythmic pattern, or the rhythmic momentum.