# Grade One Music Theory - Lesson 7: Time Signatures (UK Version)

Suitable for: ** ABRSM Grade 1 Trinity Grade 1 GCSE AP Music Theory Beginners **

## Time Signatures

A time signature is a symbol which we write at the beginning of a piece of music to show how many beats there are in one bar.

Time signatures are made of two numbers, one on top of the other.

Here's a time signature:

Time signatures are written after the clef and key signature, and only appear at the beginning of a piece of music, not on every stave.

## Grade One Music Theory Requirements

In Grade 1 music theory (ABRSM and Trinity boards) you need to know three time signatures:

## The Bottom Number

The bottom number in a time signature tells you the **type **of beat we need to count in each bar.

The number 4 represents a crotchet beat. So, in Grade One music theory we only need to think about counting crotchets, because the lower number is "4" in all three time signatures you need to know at this grade.

## The Top Number

The top number tells us **how many** beats we need to count in each complete bar.

So,

means we should count two crotchet beats in each complete bar

means we should count three crotchet beats, and

means we should count four crotchet beats. This time signature is sometimes shown with the letter "C" instead of 4/4. It's often called "common" time, but actually the "C" doesn't stand for "common" - its history dates back hundreds of years, to before modern time signatures were invented.

## Bar lines

We draw vertical bar lines through the stave to divide the music up into complete bars.

(Sometimes the first and last bars of a piece can be incomplete, but all the bars in between must be complete ones).

Here's an example in 2/4:

The values of the notes in each bar always add up to two crotchet beats.

Here's an example in 3/4. This time the first bar is incomplete:

The values of the notes in each bar add up to three crotchets, except in the first and last bars which are incomplete.

## Working out the Time Signature

In the Grade 1 music theory exam, you might have to work out the time signature of a short piece.

Don't forget that in the exam, you only need to know 2/4, 3/4 and 4/4, so the right answer must be one of these three.

To work out the time signature, add up the note values in one bar, counting a crotchet as 1.

Remember that a quaver = ½ a crotchet, a semiquaver = ¼, a minim=2 crotchets and a semibreve = 4. Also, don't forget that a dot increases the length of a note by half of its value.

When you are practising, write them out, like this:

Count up the notes in each bar, and work out how many crotchets each bar is worth.

Bar 1 is worth four crotchets (and so are all the others). Four crotchets per bar means the time signature is 4/4.

Here's another example:

There are 2 crotchet beats per bar, so this is 2/4 time.

## Adding Missing Bar Lines

In your music theory exam, you might have to add the missing bar lines to a short tune with a given time signature.

Let's work out where to put the barlines in the following melody. Use the same method: count the crotchet beats. The first bar line has been given.

First, look at the time signature. How many beats do you need to count? (Don't forget, the top number on the time signature tells us how many to count.)

In this melody, the time signature is 3/4, so we need to count **three** crotchets in every bar.

It's a good idea to pencil the note values in as you do this exercise - it's easier to work out where you've made a mistake and to double check your answers if you've done so. Let's pencil in those note values:

Start by grouping together fractions to make up complete beats.

Then add the beats together, until you reach the number you need - remember it will always be 2, 3 or 4 crotchets in the Grade One music theory exam.

Then draw a bar line, (use a ruler for neatness).

After each bar line you draw, start counting again. Repeat the process until you get to the end of the melody.

Your last bar should also have the full number of beats (in the Grade One music theory exam that is, but not always in real life!) Double check your answer - go back and count each bar again. If one of your bars has a different number of beats to the others, you have made a mistake!

Make sure that your bar lines are totally vertical (not leaning to one side or the other), that they don't poke up higher or lower than the staff, and that they are placed about one note-head's width away from the note on the right. Look at the first bar line that you were given as an example, and use it as a guideline.

Click here for a complete time signature chart (includes all time signatures - not just those on the grade 1 syllabus!)