Repetition and variation

In the first eight bars of a French folk tune from 1761, only four bars contain material that has not been heard before.

Listeners need something to hold on to. If every bar of a song brings new notes, the ear cannot predict anything and the tune slips away. If every bar is the same, it gets dull after a few seconds. Songwriters work between those two extremes: they present a short idea, repeat it so it sticks, and then change it so the song keeps moving. This unit shows three tools for doing that: exact repetition, variation and sequence.

The motif

The smallest idea that is still recognisable is called a motif (or motive): a few notes with a clear rhythm, often just one bar long. A motif is like a word that the song keeps using. In the song maker, a motif is the pattern of cells in one bar. The panel under the grid compares every bar with the bars before it and reports what it finds.

Exact repetition

The simplest tool is to play the same bar or the same two bars again. Repetition helps people learn a tune after one hearing, and it is why children's songs and chants are so easy to join in. In the grid, the button that copies bars 1 to 4 into bars 5 to 8 makes a whole half of the song repeat at once. On its own, that sounds unfinished, which is a problem the question and answer unit solves.

Variation

A variation keeps part of an idea and changes the rest. You can keep the rhythm and change the notes, keep the notes and change the rhythm, or keep the first half of the bar and change the ending. The listener still hears the link to the original, so the new bar sounds both familiar and fresh. A useful rule of thumb is to change one thing at a time. If you change notes and rhythm together, the link usually breaks.

Sequence

A sequence repeats a pattern at a higher or lower pitch. The rhythm and the shape stay the same, but everything moves up or down by the same number of scale steps. Sequences let a melody travel somewhere while still sounding organised. Because the grid uses only scale notes, moving a pattern up one row keeps it in the key automatically. The panel marks a bar as a sequence when it has the same rhythm as an earlier bar and every note has moved by the same number of rows.

Try it

Press Play and read the Repeats line in the panel. Bars 5 and 6 are bars 3 and 4 moved one row up, a sequence, and bars 7 and 8 repeat bars 5 and 6 exactly. Now make your own version: change one note in bar 8 but keep its rhythm, and watch the Repeats line stop showing "bar 8 = bar 6" and report a rhythm match or a sequence instead. Then clear the grid, write one bar, and build eight bars from it using a repeat, one variation and one sequence.

On the staff above, the first four notes are bar 3 and the last four are bar 5. Every note in the second group sits one line or space higher, which is exactly what a sequence one step up looks like on paper.