Tempo

Tempo in Western Music

Before the invention of the metronome, tempos in western European music were often inferred from the style of music performed. The speed of various types of music, especially dance music, was common knowledge. Thus, composers did not necessarily need to indicate a tempo on the written score. Around the 18th century, Italian terms became increasingly common for indicating tempo, though the subjectivity of those terms could be a source of confusion. Some of the most common terms are: largo, “very slow”; adagio, “slow”; andante, “moderately slow”; allegretto, “moderately fast”; allegro, “fast”; and presto, “very fast.”

While it is clear how these terms relate to each other, the exact meaning of “moderately slow” is subjective. Such terms are, however, not without foundations in human physiology and psychology. Andante or any other type of moderate tempo typically corresponds to a moderate walking speed or heart rate. With the patenting of the metronome in 1815, precise markings of the exact number of beats per minute could be made (e.g., 85 beats per minute).

Tempo ultimately depends on beat, or sense of pulse. In many types of music, a perfectly metronomic beat often strikes listeners as rigid and mechanical. Without mechanical aid, tempos fluctuate. Yet, too wide a fluctuation can result in not only the loss of the tempo, but also the loss of the beat. Periodicity, which is the perception of beats occurring at regular intervals, is therefore fundamental to tempo. Once the periodicity is established, tempos can be accelerated or decelerated for musical effect.

One prominent example of the manipulation of the tempo for dramatic expressive effect is rubato. In rubato (meaning “robbed” or “stole” time), the relationship among the rhythmic note-values is altered by acceleration or deceleration, such that the tempo becomes more flexible. Although a free and flexible pulse is common in many musical traditions, and is even written about in western European music as far back as the 17th century, it is most often associated with the playing styles of 19th-century piano virtuosi such as Franz Liszt and Frederic Chopin. While early instances of rubato consisted largely in only minute changes in rhythmic values while the tempo remains constant, the later 19th-century Romantic use of rubato often took more liberties with the tempo.

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