Rhythm

Rhythm is the pattern of sound, silence, and emphasis in a song. 

Rhythm usually refers to the recurrence of notes and rests (silences) in time. When a series of notes and rests repeats, it forms a rhythmic pattern. Rhythm indicates when notes are played, musical rhythm also stipulates how long they are played and with what intensity. 

Rhythm functions as the propulsive engine of a piece of music, and helps give a composition structure. 

Most musical ensembles contain a rhythm section responsible for providing the rhythmic backbone for the entire group. Drums, percussion, bass, guitar, piano, and synthesizer may all be considered rhythm instruments, depending on the context. However, all members of a music group bear responsibility for their own rhythmic performances and play the musical beats and rhythmic patterns indicated by the piece's composer. 

Different styles of music have difference rhythmic stylistic features e.g. Rock Music often has a driving rhythm, Jazz music uses a lot of syncpation. 

Features of Rhythm in Music

• Time signatures  Time signatures indicate the number of beats per measure and also how long those beats last e.g. 2/4 has 2 crotchet beats per bar and can be called simple duple, 3/4  simple triple, 4/4/  simple quadruple. 

• Meter Standard Western music theory divides time signatures into three types of musical meter: duple meter (where beats appear in groups of two), triple meter (where beats appear in groups of three), and quadruple meter (where beats appear in groups of four).

Meter is not tied to note values; for instance, a triple meter could involve three half notes, three quarter notes, three eighth notes, three sixteenth notes, or three notes of any duration.

Musicians and composers regularly mix duple and triple meter in their work e.g. Igor Stravinsky's "The Rite of Spring" OR Dave Brubecks TAKE 5 where the metre is triple/duple!

• Tempo Tempo is the speed at which a piece of music is played. 

Beats per minute (or BPM) indicates the number of beats in one minute. This isusually written above the first bar of the music.  

Composers use Italian words like largo, andante, allegro, and presto to convey tempo, describing the speed of the music. Some composers indicate tempo with words such as “fast,” “slow,” “lazy,” “relaxed,” and “moderate.”

• Strong beats and weak beats Rhythm combines strong beats and weak beats. Strong beats include the first beat of each measure (the downbeat), as well as other heavily accented beats. Both popular music and classical music combine strong beats and weak beats to create memorable rhythmic patterns. Some styles such as Reggae are characterised by emphasising weak beats (2 and 4) with a melody over the top.

• Syncopation Syncopated rhythms are those that do not align with the downbeats of individual measures. 

A syncopated beat will put its emphasis on traditional weak beats, such as the second eighth note in a measure of 4/4. Complex rhythms tend to include syncopation. While these rhythms may be more difficult for a beginning musician to pick up, they tend to sound more striking than non-syncopated rhythmic patterns.

• Accents  Accents refer to special emphases on certain beats. To understand accents, think of a piece of poetry. A poetic meter, such as iambic pentameter, may dictate a specific mixture of stressed syllables and unstressed syllables. Musical accents are no different. Different rhythms may share a time signature and tempo, but they stand out from one another by accenting different notes and beats e.g the opening bars of WE WILL ROCK YOU.

• Polyrhythms To achieve a particularly ambitious sense of rhythm, an ensemble may employ polyrhythm, which layers one type of rhythm on top of another e.g. a salsa percussion ensemble may feature congas and bongos playing 4/4 time, while the timbales concurrently play a pattern in 3/8.

This creates a dense rhythmic stew and, when properly executed, it can yield incredibly danceable rhythm patterns. Polyrhythms originated in African drumming, and they’ve spread to all sorts of genres worldwide, from Afro-Caribbean to Indian to progressive rock, jazz, and contemporary classical.