Compound Time Signatures

Table of Note Names UK v. USA

Simple Time Signatures

Up till now you have only learnt about simple time signatures. (Perhaps you didn’t think they were very “simple” though!)

A simple time signature is one where:

• the top number in the time signature is 2, 3 or 4
• the main beat is divided into two
• the main beat is not a dotted note
• the bottom number of the time signature tells you what type of note is used for the main beat

.

For example, in 4/4 the main beat is a crotchet. If we want to divide the crotchet, we split it into two quavers:

 

In 2/2, the main beat is a minim. We can split each one into two crotchets:

  

And in 3/8, the main beat is a quaver. We can split each one into two semiquavers:

 

Compound Time Signatures

Compound time signatures are new for grade three theory. A compound time signature is one where:

• the top number is 6, 9 or 12
• the main beat is divided into three
• the main beat is always a dotted note
• the bottom number shows you the division of the beat, not the main beat.

Here are the three compound time signatures you need to know for grade three theory:

 

6/8

The bottom number 8 tells us to count quavers, the top number tells us there should be 6 in a bar. But, the main beat is not quavers – because that would give us six beats in the bar. (There are always, 2, 3 or 4 beats per bar, or an irregular number which doesn’t divide into 2, 3 or 4, such as 7).

We need to work out what note value is equal to three of the notes in the time signature: what are 3 quavers worth?

Three quavers = one dotted crotchet.

Each bar has two dotted crotchet beats.

In fact,  the main beat in any /8 time is the dotted crotchet.

The quavers should always (whatever the time signature) be beamed to make complete beats whenever possible:

This grouping is wrong, because the quavers are grouped to make three beats, instead of two. (This grouping would be fine for 3/4 time, which has three beats per bar).

 

9/8

There are 9 quavers per bar.

 Each group of three quavers makes one main beat, which is worth a dotted crotchet.

There are three dotted crotchet beats per bar.

Here you can see the dotted crotchet main beats, which are then each sub-divided into three quavers. The quavers are beamed in threes, to make up one complete beat each.

 

 

12/8

There are 12 quavers per bar.

Each group of three quavers makes one main beat, which is worth a dotted crotchet.

There are four dotted crotchet beats per bar. The quavers are beamed to make it easy to see that there are four beats per bar.

 

Remember! An undotted note is always split into two. A dotted note is always split into three.

 

Duple, Triple and Quadruple Time

All the time signatures that we’ve learnt so far can be described as duple, triple or quadruple.

These words refer to the number of main beats per bar.

In simple time, it’s very easy to work out – just look at the top number.

2=duple, 3=triple and 4=quadruple.

• 2/2 and 2/4 are duple time
• 3/2, 3/4 and 3/8 are triple time
• 4/2 and 4/4 are quadruple time

 In compound time, you need to count the number of main beats, or you can divide the top number by 3.

• 6/8 is duple time (2 dotted crotchets per bar)
• 9/8 is triple time (3 dotted crotchets per bar)
• 12/8 is quadruple time (4 dotted crotchets per bar)

 

Here’s all that information summarised in a table:

(Top Number)	Duple	Triple	Quadruple
Simple	2	3	4
Compound	6	9	12

 

Time Signatures Exercises

Hover your mouse over the questions (tap on mobiles) to reveal the answers.

(Questions marked * are for ABRSM candidates only)

Exercise 1

Describe each of these time signatures as

• Simple or Compound
• Duple, Triple or Quadruple

1. 3/8simple triple
2. 6/8compound duple
3. 9/8compound triple
4. 12/8compound quadruple
5. 2/4simple duple
6. 3/4simple triple
7. 4/4simple quadruple
8. 2/2simple duple
9. 3/2simple triple
10. 4/2simple quadruple*

Exercise 2

Complete the following (E.g. The time signature 3/4 means that there are three crotchet (quarter note) beats per bar.)

1. The time signature 2/4 means that there are __________________two crotchet (quarter note) beats per bar.
2. The time signature 3/2 means that there are ___________________three minim (half note) beats per bar.
3. The time signature 12/8 means that there are _________________four dotted crotchet (dotted quarter note) beats per bar.
4. The time signature 3/8 means that there are __________________three quaver (eighth note) beats per bar.
5. The time signature 6/8 means that there are __________________two dotted crotchet (dotted quarter note) beats per bar.
6. *The time signature 4/2 means that there are __________________four minim (half note) beats per bar.

Exercise 3

Add the missing bar lines to these melodies, which all begin on the first beat of the bar.

 

 

 

 

 

 

Exercise 4

Add the time signature to each of these melodies.

 

*