Simple meter: 2/4, 3/4 and 4/4

A march steps in 2, a waltz turns in 3 and most pop songs count in 4; in all three the beat splits into two equal halves.

Grouping beats into bars

Beats are not all equal. In most music some feel heavier than others, and the heavy ones come back at a regular distance. Meter is this pattern of strong and weak beats. When beats group in twos, the meter is duple: strong, weak, strong, weak, the pattern of left-right marching. Groups of three make triple meter, the turn of a waltz: strong, weak, weak. Groups of four make quadruple meter, strong, weak, medium, weak, with a second, lighter accent on beat 3. A bar or measure holds one group, and a vertical bar line marks where each group ends.

The second question is how each beat divides. In simple meter each beat splits into two equal parts, counted "1 & 2 &", and then into four, "1 e & a". Duple, triple and quadruple describe the grouping; simple describes the division. So 2/4 is simple duple, 3/4 simple triple and 4/4 simple quadruple. The next unit covers compound meter, where each beat splits into three instead.

Reading a time signature

The time signature at the start of a piece is two stacked numbers. In simple meters the top number is the number of beats in a bar, always 2, 3 or 4, and the bottom number names the note that gets one beat: 4 for a quarter note, 2 for a half note, 8 for an eighth note. So 3/4 means three quarter-note beats per bar, and 3/8 means three eighth-note beats. 2/2, often written as a C with a vertical line through it and called cut time, means two half-note beats per bar. The written notes can look the same in 2/2 and 4/4, but in 2/2 you count and feel two beats, which sounds lighter and faster.

Conducting and feeling the meter

Conductors show the meter with the shape their hand draws in the air. Beat 1 is always a straight drop downward, which is why the first beat of a bar is called the downbeat. The last beat always rises back up, the upbeat. In between, a pattern in 3 moves out to the right on beat 2, and a pattern in 4 crosses in to the left on beat 2 and out to the right on 3. Drawing the pattern while you listen is a good way to find the meter of a song: if the downbeat keeps landing at the start of every group of three, you are in 3.

A double bar line marks a boundary: two thin lines separate sections, and one thin line followed by a thick one ends the piece. A pair of dots in front of a double bar means repeat. Inside a bar, the faster pulses are counted with syllables: "1 & 2 &" for eighth notes in 2/4, "1 e & a 2 e & a" for sixteenths. Counting out loud with these syllables is how players keep long notes and rests the right length, since the voice keeps moving even when the instrument is silent.

Use the metronome tab to hear the difference. Choose 3/4 and listen to the high click on beat 1 followed by two lower clicks; then switch to 4/4 and notice the medium accent on beat 3. Turn on Divisions to hear the "&" between beats. In the Tap along tab there is a waltz rhythm in 3/4 and a march rhythm in 2/4 to tap.