There is much more to say about rhythm than what I will be exposing in this post. However, I am assuming that you already know enough about rhythm figures, meter and pulse, to follow along.
Depending on certain music genres, rhythm can be one of the most defining characteristics of that genre – see Blues, Funk, Rock, Jazz, and music from different cultures. Rhythm is the time element of music and it is related to tempo, to the duration of sounds and to its rhythmic patterns and variations over time. It is an interplay of sound and silence.
Usually we hear these patterns in relation to a steady pulse and mentally organize this pulse into a meter, dividing them into beats per measure or bar. Rhythm is not an exclusive element explored by percussive instruments as melodies also have implied rhythm. Ultimately, it is how we can control the melodic flow and maintain interest.
But rhythm is not present only in music. In poetry, words can be arranged in a more or less regular sequence and/or according to long or short syllables that altogether form a cadence, a metrical movement and rhythmical form; in painting, sculpture or architecture, with alternating patterns of light and shade, of colors, of mass and void, etc; or in film, with the length of the scenes, speech timing, recurring themes.
All in order to create movement, tension and emotional value in the development of the plot. Any sequence of a regularly occurring event such as the heartbeat, may imply rhythm, beats or pulse. That said, how rhythm and other musical elements may be present in other art forms is something to be mindful about as it provides endless material and inspiration for your music compositions – also see musical metaphors.
Rhythm and Expression
Several studies in the field of Music Psychology show that modulating certain aspects of the musical elements of a given musical piece induces emotional responses in the listeners that can actually be measured. For instance, it has been found that powerful external rhythms influence the internal bodily rhythm (i.e. increased heart rate), and that in time the body rhythm adjusts to the external stimulus.
In turn, this internal adjustment induces a certain emotional response or feeling in the listener. This happens with other musical elements as well, like the type of scale a melody is based upon, degree of dissonance or consonance in chords, etc.
Apart from how loud a certain rhythm can be played, this element can be explored in other expressive ways. Perhaps the most obvious one would be manipulating tempo by performing a rhythmic phrase slower or faster. There are many experimental results confirming that tempo clearly determines whether music sounds sad or happy.
Words like “stressing” or “amusing” are related to high tempo music while the terms “relaxing” or “boring” are associated to low tempo. This indicates that changing tempo alters the perception of the emotional value from a given musical cue. Also, music with higher rhythmic units, like sixteenth notes, is attributed similar emotional value as music with high tempo, while lower rhythmic units, such as whole and half notes, correlates to low tempo music.
The following table shows some of the findings that are common to many of such studies in the field of Music Psychology:
Another important feature associated to tempo is that it doesn’t have to be locked, meaning that you can gradually increase or decrease tempo (beats per minute) – Accelerando or Ritardando, respectively. This is a way of manipulating the listener’s emotional perception of music from a sense of stillness to an impending tragedy.
The theory of ebb and flow suggests that arousal and emotional responses can be induced in a listener because of a specific feature of music that violates, delays, or confirms the listener’s expectations about the continuation of the music.
This means that introducing novelty and variations in music, in this case using the rhythm element, is a key factor to maintain interest, evoke emotional responses and convey a message – although not introducing any novelty at all can also be uses as means to express something.
BEYOND MUSIC THEORY 