Rhythm is everything that has to do with organization of musical elements in time. Rhythm includes pace, tempo, meter and an almost infinite number of ways in which long or short durations of sound and silence make up patterns in time. These manipulations of meter to form patterns are important factors because they are the primary means of providing both tension and repose. There are many pattern devices in which tension can be created, such as meter alterations and ostinato. An examination of which specific actions taken with pace, tempo, and meter create either tension or repose is in order to define how rhythm itself creates these feelings in the listener.
A sense of repose results when some one element supplies unity by remaining unchanged while the other elements are changing dramatically. The stability of this rhythm provides a norm for the listener that suppresses the tension. However, when rhythm is subjected to considerable variation, the unpredictability of the variation and the increased amount of information the listener must process can generate a great deal of tension.
Musical pulse is a series of undifferentiated impulses all of equal length and emphasis. People usually perceive these pulses in groups of two or three, because of stresses or accents (real or imagined) at the start of the first pulse of each group. There are usually pulse groups at more than one level of a piece; sometimes there are different pulses at several levels simultaneously. For instance, Giuseppe Tartini’s Symphony in A Major, third movement, has a great deal of activity in the violins at a pulse rate twice as fast as that of each basic pulse. This results from dividing each basic pulse into two parts.
Pace is the rate of activity for any musical element, perceived in relation to some norm. Once that norm is established, any increase or decrease in the rate at which sounds change is a change in pace. Increasing the pace of any element increases the level of tension. For instance, speeding up the pulse, increasing the volume, and changing the quality of the sound all increase the tension. However, decreasing the rate of any of these creates a sense of repose. For instance, in John Coltrane’s A Love Supreme, the changes in pace coincide with the points of greatest tension. The solo develops while increased activity is added to the constant background of drums, bass and piano. The greatest level of tension is created by playing higher pitches at a faster pace, while the greatest level of repose is created by slowing the pace and playing lower pitches.
Tempo is the relative speed of a piece as marked by the number of pulses within a given time span. The more basic pulses within a given time span, the faster the tempo. A normal heart rate is seventy-two to seventy-six pulses per minute, and as a rule of thumb, tempos close to a normal heart rate can be considered a moderate speed. Tempos on either side can be considered faster or slower. Unconsciously, listeners expect a steady state as a norm in a piece of music. Changes in tempo intrude strongly on our awareness and produce tension or repose. For instance, familiarity with a steady sense of pulse in a particular musical tradition such as classical or jazz, can create expectations. If these expectations are denied, the level of tension is heightened. If the expectations are fulfilled, the level of tension will be considerably lower. There are four kinds of tempo change: an abrupt shift in the basic pulse rate, accelerando, ritardando, and rubato. Accelerando is a gradual increase in the basic pulse rate. Ritardando is a gradual decrease in a basic pulse rate. Both accelerando and ritardando help provide smooth transitions. Rubato is a constant give-and-take in a basic pulse rate. Abrupt tempo shifts such as rubato have dramatic effects, heightening or lowering the tension suddenly and intensifying the impact of a musical idea. Since any change in a basic pulse rate is easily perceived, composers use tempo changes for a variety of effects, such as changing the mood or the beginning or end of a musical idea.
Meter is the marking of musical time by musical pulses, which can operate separately or become building blocks for larger metrical groupings. There are three types of metrical conflict – syncopation, superimposed subdivision, and suppressed meter. They always create conflict or ambiguity, which increases the level of tension in a musical piece. Syncopation is the unexpected absence or displacement of the normal first-pulse accent that defines the basic meter group. It is one of the most common tension-raising devices in music. Many syncopated rhythms placed together can create great excitement for the listener. For example, in Peter Ilich Tchaikovsky’s Swan Lake “Valse”, the normal accent of the fast three-pulse basic meter is contradicted by repeated stress on the second pulse of the group while the basic pulse continues. Superimposing a new subdivision on a well-established meter level creates metrical conflict because it increases the number of musical events the listener must deal with at one time. This device is used sporadically throughout a piece because its effectiveness relies on the surprise of contrast the added subdivision provides to what has preceded it. For instance, Charles Ives’ Symphony No. 3 is a clear example of how much tension can be created through superimposed subdivision. The basic pulse remains constant, however, the listener’s attention shifts from instrument to instrument when they create conflicting metrical groupings. Suppression of strong musical emphasis leads to ambiguity and uncertainty, which is a source of musical tension. Changing the pulse groups from twos to threes and vice versa can result in an increase or decrease in tension and a heightening of rhythmic interest. Unequal time spans are created by mixing two-pulse and three-pulse groupings in many pieces. This raises the level of tension because our musical conditioning leads us to expect that time will be marked off equally (denying this expectation increases tension) and such mixtures are harder to keep track of than consistent repetition of the basic pulse groups.
A device known as the ostinato is a rhythmic pattern that becomes recognizable by being repeated persistently throughout a composition. It is often fused with a melody and serves as a rhythmic backdrop in certain pieces of music. Its principle of unity through repetition remains the same though the pattern of any ostinato is often unique to the particular composition to which it occurs. For instance, dance rhythms require fixed tempo, meter, and rhythmic patterns that accompany the steps of a specific dance. To a point, repetition of an ostinato can produce security and repose, beyond that point repetition tends to raise the level of tension by its very insistence. Ostinato as an accompaniment can be another source of tension. In concert music, a composer may keep the essence of a dance’s particular rhythms, but will change the basic pattern. The listener’s familiarity with the basic pattern creates expectations that the composer may or may not choose to fulfill, creating a rich source of interest and tension.
To instill a feeling of tension, a composer can speed up the pulse, increase the volume, change the quality of the sound, deny a listener’s expectations of a particular style, use rubato, accompany with ostinato, use unequal time spans or create metrical conflict such as syncopation (one of the most common techniques), superimposed subdivision or suppressed meter. To create a sense of repose, a composer may slow down the pulse, decrease the volume, maintain the sound quality, stick to the traditional style of a genre, use accelerando or ritardando, use equal time spans or repeat an ostinato. These are all examples of how a composer can alter the pace, tempo or meter of a piece, or the rhythm, to create feelings of either tension or repose.
Funes, Donald J. Musical Involvement: A Guide to Perceptive Listening, 2d ed. Toronto: Harcourt Brace Jovanovich, 1992
Giuseppe Tartini: Symphony in A Major, 3rd movement (excerpt). Zurich Chamber Orchestra; Edmond de Stoutz, conductor.
John Coltrane: A Love Supreme, 1st movement (exerpt). John Coltrane, saxophone.
Peter Ilich Tchaikovsky: Swan Lake, “Valse” (excerpt). Philadelphia Orchestra; Eugene Ormady, conductor.
Charles Ives: Symphony No. 3, 2nd movement (excerpt). New York Philharmonic; Leonard Bernstein, conductor.