Asymmetric time signatures and beat grouping

22 min

A limping waltz and a war march

In 1893 Tchaikovsky wrote the second movement of his Sixth Symphony with five crotchets in every bar. It sounds like a waltz that has one foot shorter than the other. Twenty years later Gustav Holst used the same five-beat bar for "Mars, the Bringer of War" in The Planets, and in 1959 the Dave Brubeck Quartet recorded "Take Five", the best-known jazz tune in five-four. None of these bars divides into equal beats. They are asymmetric.

Definition

Asymmetric time (irregular or odd time): time in which the beats of a bar are not all the same length. The bar is built from groups of two and three quavers (or crotchets). Examples: five-eight (2 + 3 or 3 + 2), seven-eight (2 + 2 + 3, 2 + 3 + 2 or 3 + 2 + 2), five-four.

Beat grouping: the way the quavers of a bar are gathered into beats. It is shown by the beaming, and sometimes by numbers such as 2 + 3 printed above the time signature.

Five-eight: one short beat, one long beat

A bar of five-eight holds five quavers. Five cannot be split into equal twos or equal threes, so it is felt as two beats of different length: a short beat of two quavers and a long beat of three. The beaming tells you which comes first.

Say a two-syllable word for each short group and a three-syllable word for each long one. For 2 + 3: "Hu-ye, Mu-sa-nze". For 3 + 2: "Mu-sa-nze, Hu-ye". Stress the first syllable of each word; that is where the accent (>) falls.

Seven-eight: three beats, one of them long

Seven quavers are usually felt as three beats: two short and one long. The long beat can come last (2 + 2 + 3), in the middle (2 + 3 + 2) or first (3 + 2 + 2). Bulgarian dance music is famous for this metre: the rachenitsa, for example, is counted in seven quick pulses grouped 2 + 2 + 3.

Time signature	Common groupings	Beats felt	Conduct in
five-eight	2 + 3, 3 + 2	2 (short, long or long, short)	2
seven-eight	2 + 2 + 3, 2 + 3 + 2, 3 + 2 + 2	3 (one of them long)	3
five-four	3 + 2, 2 + 3 (crotchets)	2 groups, or 5 at a slow tempo	2 or 5

When a conductor beats an asymmetric bar, the long beat takes visibly longer to travel than the short ones, so the players can see where the three-quaver group falls.

Worked example

Worked example 1: find the grouping from the beaming. A bar of seven-eight shows quavers beamed 3, then 2, then 2.

Step 1. Each beamed group is one beat: 3 + 2 + 2 = 7 quavers.

Step 2. The long beat (three quavers) comes first.

Answer: count "1 2 3 1 2 1 2", with accents on the 1s; say "Mu-sa-nze Hu-ye Hu-ye".

Worked example

Worked example 2: notate a grouping with longer notes. Write one bar of five-eight grouped 2 + 3 using only two notes.

Step 1. The short beat is two quavers long: a crotchet.

Step 2. The long beat is three quavers long: a dotted crotchet.

Answer: crotchet, then dotted crotchet. Check: 2 + 3 = 5 quavers. (Writing the dotted crotchet first would give 3 + 2 instead.)

Perform it

Here is a short melody in seven-eight, written for this lesson. Every bar is grouped 2 + 2 + 3.

Clap the rhythm only, counting the numbers under the notes aloud. Clap louder on every 1.
Say the sol-fa names (C = d, D = r, E = m, F = f, G = s, A = l) in rhythm.
Sing or play it on a keyboard or recorder, keeping a steady quaver pulse. Then try it with a partner tapping only the accented 1s on a drum.

Video: "Odd Time Signatures • 5/4, 5/8, 7/8", Godfrey Guitar. Listen for how each bar is broken into groups of two and three, and count along with the examples.

Tip

Twos and threes, nothing else. Any asymmetric bar is just a chain of two-quaver and three-quaver beats. Find the threes, and the bar becomes easy to count.

Warning

Common mistake: counting seven-eight "1 2 3 4 5 6 7" evenly. It loses the shape of the music. Count the groups ("1 2 1 2 1 2 3") so the accents land where the composer wanted them.

✦

Practice

Define asymmetric time in one sentence.
Write two different groupings for five-eight.
How many beats are felt in a bar of seven-eight grouped 2 + 2 + 3? Which beat is the long one?
Write the count under a bar of seven-eight beamed 2 + 3 + 2.
Using a crotchet and a dotted crotchet, write one bar of five-eight grouped 3 + 2.
Is nine-eight asymmetric? Explain using its usual beaming.
Compose one bar of seven-eight grouped 3 + 2 + 2 that uses at least one rest. Check that your values add to 7 quavers.
Explain why a conductor can beat five-eight in 2 but not with two equal movements.

Show answersHide answers

Time in which the beats of a bar are of unequal length, built from groups of two and three.
2 + 3 and 3 + 2.
Three beats; the third (the group of three quavers) is the long one.
"1 2 1 2 3 1 2".
Dotted crotchet, then crotchet (3 + 2 = 5).
No. Its nine quavers are normally beamed 3 + 3 + 3, three equal dotted-crotchet beats, so it is compound triple time.
Many answers. Example: dotted crotchet rest, crotchet, quaver, quaver (3 + 2 + 1 + 1 = 7).
One beat lasts two quavers and the other three, so one movement must take longer than the other.

Remember

Asymmetric bars mix beats of two and three quavers.
Five-eight = 2 + 3 or 3 + 2. Seven-eight = 2 + 2 + 3, 2 + 3 + 2 or 3 + 2 + 2.
The beaming shows the grouping; the accent falls on the first quaver of each group.
Count the groups, not the quavers in a row.

1A limping waltz and a war march

2Five-eight: one short beat, one long beat

3Seven-eight: three beats, one of them long

4Perform it

A limping waltz and a war march

Five-eight: one short beat, one long beat

Seven-eight: three beats, one of them long

Perform it