Note lengths and metre
- The time signature shows the metre: the top number is how many beats are in a bar, and the bottom shows the type of beat.
- Simple time divides each beat into two: 2/4, 3/4 and 4/4. Compound time divides each beat into three: 6/8 has two dotted-crotchet beats.
- Irregular metres have unusual groupings, such as 5/4 or 7/8.
Rhythmic devices
- Syncopation puts the accent off the beat, making music feel lively, as in jazz and pop.
- Dotted rhythms have a long note followed by a short one, giving a jagged feel.
- Triplets fit three notes into the time of two.
- Swing rhythms play pairs of quavers unevenly (long-short), as in jazz.
- Cross-rhythms play two different rhythms against each other at the same time.
- A hemiola makes two bars of 3/4 feel like three bars of 2/4.
Tempo
- Tempo is the speed of the music, often measured in beats per minute (bpm).
- Largo: very slow. Adagio: slow. Andante: at a walking pace. Moderato: at a moderate speed. Allegro: fast. Presto: very fast.
- Accelerando: getting faster. Rallentando (or ritardando): getting slower. Rubato: stretching the tempo for expression. A pause (fermata) holds a note longer than written.
Key terms
- Time signature
- Numbers showing the beats in a bar and the type of beat.
- Syncopation
- Accents off the beat.
- Compound time
- Metre where each beat divides into three, such as 6/8.
- Triplet
- Three notes played in the time of two.
- Tempo
- The speed of the music.
- Allegro
- Fast.
- Rallentando
- Gradually getting slower.
- Rubato
- Stretching the tempo freely for expression.