Bars and time signatures
Read a time signature and group beats into bars.
Beats are not just counted forever: they are grouped. The group is called a bar, and the time signature says how big it is.
Bars
Beats are grouped into bars, also called measures. Bars are separated by vertical lines called barlines. A double barline marks the end of a section; a thick final barline marks the end of the piece.
The time signature
The time signature is two stacked numbers at the start of the music:
- the top number tells you how many beats are in each bar;
- the bottom number tells you which note value counts as one beat: 4 means a quarter note, 2 a half note, 8 an eighth note.
Rhythm diagrams on this site use a single line instead of a staff: the notes sit on the line and the beat numbers are written under them.
Common time signatures
- 4/4: four quarter-note beats per bar. By far the most common in pop, rock, funk and jazz. It is also written C, and called common time.
- 3/4: three quarter-note beats per bar, the waltz.
- 2/4: two quarter-note beats per bar, marches and polkas.
- 2/2: two half-note beats per bar. It is written with the symbol ¢ and called cut time. It looks like 4/4 on paper but is felt in two.
These are simple meters: each beat divides naturally into two. Meters such as 6/8 and 12/8, where each beat divides into three, come in Module 11.
Filling the bar
A bar does not have to contain one note per beat. The note values in each bar just have to add up to the time signature, as the second bar above shows.
Count “1 2 3 4” with a metronome and play the open E only on beat 1 of each bar. Then switch to “1 2 3”, still playing only on beat 1. Feel how the bar changes.