Measures (bars) – How many beats in a bar
Musical notes on a staff are grouped in measures, or also called bars (I will use both terms in this lesson). How many beats in a bar there are? Well, that depends on the time signature, as we will see soon.
How many beats in a bar (or measure)?
You can often hear musicians that play together count 1 – 2 – 3 – 4 before the song starts. What they are counting, are actually the beats in a measure. Most songs have 4 beats in a bar. You can count 1 – 2 – 3 – 4 – 1 – 2 – 3 – 4 – … during the whole song (when the time signature doesn’t change during the song).
Another common type of songs has 3 beats in a measure. A waltz is an example of a piece with 3 beats per measure.
Those two types (4 beats in a bar and 3 beats in a bar) are most common, but other numbers of beats in a bar are also possible.
Time signature – 4 quarter time
Let’s again have a look at songs that have 4 beats in a measure. You remember probably that a quarter note has a duration of exactly one beat. So that means that instead of saying 4 beats per measure, you could also say: 4 quarter notes per measure. A piece of music that has 4 quarter notes per measure is called a piece in 4 quarter time. Or, you can also say: the time signature is 4 quarter.
In sheet music, in the beginning of a piece, we write this as follows (after the treble or bass clef):
Since 4 quarter is the most common time signature, it’s also very often written as follows:
Now, 4 quarter notes per bar doesn’t mean that you can only have quarter notes. It means that all the note durations of the notes in one bar added together make 4 beats. For example, 1 bar can consist of one whole note, or 2 half notes, or a half note with 2 quarter notes. One bar can have 8 eighth notes, or 4 eighth notes and 2 quarter notes, etcetera, as long as the total duration is that of 4 beats.
Let me give an example of 4 quarter time music. In the next staff, 2 bars of a little musical line are written out. Note that the bars are separated by vertical lines.
For a good understanding of the music, it’s important to know on which beat the notes in a song are. To know this, you can count 1 – 2 – 3 – 4 – 1 – 2 – 3 – 4 etcetera during the whole song. In the next sound sample, you will hear the musical line written in the staff above. The metronome will count to 4 before the song starts. Count 1 – 2 – 3 – 4 – 1 – 2 – 3 – 4 – 1 – 2 – 3 – 4 with the metronome and pay attention which notes in the staff are exactly on beat 1, beat 2, etcetera.
When you do it well, you should come up with the following:
Time signature – 3 quarter time
We already know how many beats in a bar the 3 quarter time signature has: that’s 3 beats, or 3 quarter notes. But any other combination of note lengths can be made that add up to 3 quarter notes, of course. So, 1 quarter note plus 4 eighth notes, or 2 quarter notes and 2 eighth notes, etcetera.
The symbol for the 3 quarter time signature that has to be placed in the beginning of the staff is:
Here’s the first line of “Amazing grace”, which is in 3 quarter time:
You might notice a strange thing: the first measure only has 1 quarter note, when it should be 3! This happens quite often in the beginning of a song: the song actually starts on beat 3 instead of on beat 1. We call this first measure with only one quarter note a pickup, or more oficially, an anacrusis.
Below, you can listen to a sound sample of the first line of Amazing grace. The metronome begins by counting to 3 (because it’s 3 quarter time), then it starts again to 3. The pickup note (the G) is then played on beat 3. So, this means that you will hear the metronome count 5 times before the first note plays.
Other time signatures
There are many other time signatures, sometimes very exotic ones, like for example 11 eighth. I will not talk about those very complicated time signatures, but let me introduce you 2 more or less common ones.
6 eighth time
In a 6 eighth time signature, you can have 6 eighth notes per bar.
How many beats in a bar is that? Well, that’s 6 beats, because every beat in a 6 eighth time signature goes with an eighth note. Now, this might be confusing for you, because in my lesson about note durations I told that a quarter note was exactly one beat… Well, this is true for all the ‘quarter time signatures’, like 3 quarter and 4 quarter. In ‘eighth time signatures’ (like 3 eighth or 6 eighth), every eighth note is exactly one beat.
In fact, the ‘8’ in 6 eighth means that every beat corresponds to an eighth note. The ‘6’ in a 6 eighth time means that you have 6 of those eighth notes in a measure.
An example of a 6 eighth time is “Norwegian wood” from the Beatles. Here’s the first line:
Now, compare this line with the sound sample of the first line of Norwegian wood:
You might ask: “What’s the difference between 3 quarter and 6 eighth? You could very well have 6 eighth notes in a 3 quarter time piece!
The difference is: which beats are accentuated?
When you have 6 eighth notes in a 3 quarter time piece, you actually have 3 times 2 eighth notes. You could count like: ‘1 and 2 and 3 and’ for the 6 notes. The accents are on beat 1, 2 and 3.
When you have 6 eighth notes in a 6 eighth time piece, beats 1 and 4 are accentuated, so there are 2 groups of 3 eighth notes in a bar. You can then count as follows: ‘1 – 2 – 3 – 4 – 5 – 6′.
5 quarter time
One of the most famous pieces in 5 quarter time is “Take five” by Dave Brubeck. How many beats in a bar has a piece in 5 quarter time? Well, 5 of course: 5 quarter notes.
Below, you can listen to “Take five” (see if you can count with the song: 1-2-3-4-5 1-2-3-4-5 etc):
I hope this lesson helped you to learn about bars and beats. Please tell us what you think of it in the comments below.