Lesson 6: Measures

Music is often divided up into units called measures or bars. Each measure has a certain number of beats. The number of beats is determined by the time signature. (Another word for time signature is meter). For example, some music is written so that every measure has four beats, and that the quarter note is the unit that "gets the beat". In such a piece the time signature would be   . We say "four four" when we read this time signature. In  time, the top '4' represents the number of beats per bar: four. The bottom '4' tells us what kind of note gets the beat. The bottom four means "quarter note".

In this lesson, we are only going to deal with three different time signatures:

          and     

There are things you will eventually need to know about all time signatures. For example, you will eventually learn that the time signatures listed above are called simple time signatures. But that's not necessary right now. All you need to know is that in each of these particular time signatures:

-the top number tells us how many beats.
-the bottom number tells us what kind of note gets the beat.

(Lesson 13 will delve into time signatures to a greater degree, and you'll learn about compound time signatures. Compound time signatures tell us the number of beats in a bar, but not in a direct way. Don't worry about it for now!)

Take a look at the following piece of music:

   

This is a piece of music that has been written in     time. That's obvious, because of the time signature at the beginning of the piece! But let's say that the composer "forgot" to put a time signature at the beginning. How would we be able to know that the piece was in  ? Well, if you count up the number of beats in each bar, you would find that each bar has three beats, and that each beat is a quarter note:

Bar1: 3 quarter notes = 3 beats.
Bar2: 4 eighth notes plus 1 quarter note = 3 beats.
Bar3: 1 half note plus 2 eighth notes = 3 beats.
Bar4: 1 dotted half note = 3 beats.

It is necessary, in any given time signature, to make sure that each bar has the same number of beats, and that the number of beats is the top number of the time signature. If we were to take the example above and write the count of each bar, it would look like this:

   

If you play a musical instrument, you are probably already familiar with "counting" in this manner.

The time signature is  . So count two beats, then draw a bar line; then count another two beats and draw another bar line. It should work out that every bar gets two beats, because that is what    means! Here's what it should look like once you've drawn the lines in:

   

Bar 1: 2 eighths plus 1 quarter = 2 beats.
Bar 2: 4 sixteenths plus 1 quarter = 2 beats, etc.....

You can see that each bar gets 2 beats. The counts have been written in. Notice that each beat gets a number (that's obvious!) In bar 1, the first eighth gets a "1". The second eighth gets a "+" to indicate that it's in-between beats one and two. In bar 2, the first sixteenth gets a "1". The next sixteenth gets an "e" (our way of showing a note that is one sixteenth past the beat). The next sixteenth is a "+" because it is one eighth past the beat. The fourth sixteenth gets a "a". (our way of showing a note that is the fourth sixteenth past the beat.) This funny way of showing the counts makes it easy to say the counts. For example, if you saw a bar of music in    that had eight sixteenth notes, you would say the count like this: "One -e- and - a Two -e- and - a". If you come across a piece of music in which the eighth note gets the beat, then each eighth note gets a number, and each sixteenth gets a "+":

Sometimes we have to write the counts into a bar that features syncopation. Syncopation occurs when the normal rhythmic stresses in a bar are changed. For example, normally in a piece of music written in    one tends to be quite aware of a "strong - weak - strong - weak" pulsing of the music. Click this play-bar to hear what we mean:    Now compare that to what you hear in this excerpt:    You can hear that the strong-weak pulses of the bar have been altered, giving some rhythmic intensity to the music. You'll revisit the topic of syncopation in Lesson 13.