Lesson 33: Time: Beats & Measures
This lesson teaches how we
measure time in music, using
beats and
measures.
The Beat
The basic unit of time that we "feel" in music is the
beat. Here are
some basic beat facts:
Each beat in a song (in most songs) lasts the same amount of time; that
is, the beat is
regular. In fact, the regular beat is what makes music
"rhythmic". The beat is the basic property of music that makes you feel like
clapping or dancing or moving with it.
Although each beat in a
single song (in most songs) lasts the
same amount of time, the speed of the beats can be very different from song to
song. This is the difference between "fast" songs and "slow" songs.
How fast is a beat? The speed of the beats is very different in
different songs; but some typical example beat speeds could be "the speed of a
heartbeat", or "the speed of your steps walking or running", or "a speed
that's comfortable to count". That last one is especially important; we often
count beats, and if you're hearing a time-span in a song which is too
fast or slow to count, then what you're hearing is probably
not the
"beat". In fact, because we often count beats,
beats are sometime
called
counts.
Tempo. The speed of the beats in a particular song is that song's
tempo. We measure tempo in
beats per minute or
BPM. Very
roughly, the "common" range of tempos in pop music is from about
60 BPM
(slow) to about
160 BPM (fast). One famous tempo is the "disco tempo",
120 BPM.
Measures
We often
count the beats when we're trying to understand a song's use
of time. Of course, we could just count beats from the beginning of the song,
like this:
1 2 3 4 5 6
7 8 9 10 ...
But, in real songs, the beats are actually
grouped into "chunks" which
we call
measures, and we count starting over with "beat 1" for each
measure, like this:
| 1 2 3 4 |
1 2 3 4 | ...
Here are some key facts about measures:
-
The vertical lines between measures are called bar lines. Written
music uses these bar lines to separate the measures. "Measures" are
sometimes called "bars" because of these bar lines.
-
The great majority of pop songs have 4 beats per measure. However,
there are exceptions:
-
Occasional songs have 3 beats per measure, which is the "waltz" feel.
Famous examples are "Open Arms" (Journey) and "Send In The Clowns"
(Sondheim).
-
Some songs have an occasional odd measure with a different number of
beats (e.g. 3, 5, or 6).
-
Rarely, a whole song may use some other number of beats per measure.
Famous examples are the "Mission Impossible" theme and "Take 5" (Dave
Brubeck) (both of these use 5 beats per measure), and "Money" (Pink
Floyd) (7 beats per measure, or "4 + 3" if you prefer).
-
Beat 1 of each measure is sometimes called the down beat.
Practicing Counting
To understand beats and measures, you can't just read about them; you must
"feel" them. Some people can do this "naturally", but other people need to
learn and practice this. The best way to learn this is simple: Just count the
beats (say "1 2 3 4, 1 2 3 4 ...") while listening to real songs. You may need
a musician to help you and tell you if you're "doing it right".
Next: