Melodic sequences and rhythm as identity – free course

Two tools will now multiply your ability to grow an idea. The melodic sequence moves a motif to other pitches and creates irresistible momentum. A characteristic rhythm gives a whole piece a recognisable signature, whatever the pitches. Bach, Vivaldi, Mozart and film composers use them constantly.

1. How a sequence works

A sequence repeats a motif several times in a row, each time shifted by the same interval (often one step, up or down). The ear grasps the process by the second occurrence and happily anticipates what follows.

M:4/4
L:1/8
Q:1/4=100
K:C
C D E C D E F D | E F G E F4 |]

The motif C–D–E–C is played three times, rising one step each time, then the phrase comes to rest. This is an ascending sequence: it creates drive and expectation.

2. The circle-of-fifths sequence

The most famous sequence in music history moves the melody and the harmony down together, following the circle of fifths: C – F – B° – Em – Am – Dm – G – C. You will find it in Vivaldi, Bach, Handel and countless songs.

M:4/4
L:1/8
Q:1/4=96
K:C
%%staves {RH LH}
V:RH clef=treble
V:LH clef=bass
[V:RH] "C"e d e c "F"f e f c | "Bdim"d c d B "Em"e d e B | "Am"c B c A "Dm"d c d A | "G"B A B G "C"c4 |]
[V:LH] C,4 F,4 | B,,4 E,4 | A,,4 D,4 | G,,4 C,4 |]

Each bar repeats the same pattern one step lower, and the bass alternates a rising fourth and a falling fifth. Notice that the sequence stays within the C major scale: it is a diatonic (tonal) sequence (the intervals adjust: the chord on B is diminished). A real sequence, by contrast, reproduces the exact intervals and therefore leaves the key; it is used to modulate.

The rule of three, again: a sequence usually runs for three statements (sometimes four), then it is "broken" by a cadence or a new idea. Any longer and it becomes mechanical — what old textbooks called a "rosalia".

3. Rhythm as a piece's signature

The same pitches with three different rhythms give three different characters: steady and calm (a), dotted and proud (b), syncopated and dancing (c).

M:4/4
L:1/8
Q:1/4=90
K:C
"^a"C2 E2 G2 c2 | "^b"C3 E G3 c | "^c"z C E2 G2 c2 |]

In a successful piece, a characteristic rhythm keeps coming back, even when the pitches change. It works as a common thread: Mozart's Rondo alla turca, Ravel's Boléro and most film themes rest on an insistent rhythm. Here is a little jig in 6/8 in which the same cell "long-short, crotchet, crotchet, quaver" gives every bar its identity:

M:6/8
L:1/8
Q:3/8=72
K:C
"C"G>A G E2 C | "F"A>B A F2 A | "G"G>A G D2 B, | "C"C3 z3 |]

Tap this rhythm with the widget: you will see that it is almost enough on its own to recognise the piece.

Common mistakes:

The endless sequence: five, six statements… the listener guessed what comes next long ago and is bored.
The sequence that leads nowhere: a sequence must take you somewhere (a cadence, a climax, a new key).
A different rhythm in every bar: without a recurring rhythmic cell, the piece has no face.
A rhythm that is too uniform: conversely, steady quavers from start to finish become monotonous; plan long notes so the music can breathe.

Your workshop

Invent a one-bar motif (4 to 6 notes) in the piano roll.
Write a descending sequence of three statements, each one step lower, then finish with a cadence on C.
Now choose a characteristic rhythmic cell (dotted, syncopated, or in 6/8) and write an eight-bar piece in which it returns in at least six bars, with different pitches.
Add a bass that follows the circle of fifths from the example (C, F, B, E, A, D, G, C) during your sequence.
Copy your best passage into the ABC editor.

Self-check: if you clap only the rhythm of your piece, can someone who has heard it recognise it?