Tempo

In this article, we will review the concept of tempo in music, including immediate and gradual changes in tempo and some common tempo markings

What is tempo?

We mentioned previously that the lengths of notes are relative to the tempo given at the beginning of the piece. It follows, then, that the tempo of a piece can be defined as the relative speed of the music’s beat pulse.

In order to change the tempo, composers have two options: they can immediately set a new tempo (called immediate tempo changes) or they can change the tempo gradually (called a gradual tempo change). Let's explore each one separately.

What is an immediate tempo change?

An immediate tempo change is used to change the tempo, well, immediately.

There must be an immediate tempo change at the beginning of a piece (including movements in a multi-movement work), and there may or may not be more throughout the work.

There are are two important parts to an immediate tempo change, though only one must be present for it to be valid:

A piece of text is usually present to indicate the relative speed of the music. Traditionally, composers have used the Italian language for this and other text in music. These can range from very slow speeds, such as largo; to slow speeds, such as adagio; moderately slow speeds like andante; moderate speeds, such as moderato; and faster speeds like allegreto, allegro, and presto. See below for a table containing all of the tempo texts that are required for the AP exam, but know that a composer could put any text they wish (even in English or another language like French or German).
A metronome marking can also appear, which identifies a note value, such as quarter note, dotted quarter note, eighth note, etc., and then labels the number of beats per minute. An example would be "Quarter note = 88." See below for examples.

This tempo change has both text and a metronome marking. The text "Presto" literally translates from Italian to "soon." In music, it means "very fast." This is backed up by the quarter note = 150 marking.

Set a metronome to 150 bpm and subdivide the beat by clapping a steady stream of eighth notes. Now, lower the beats per minute to 60. Imagine a tempo marking labeled "eighth note = 60." Is this a relatively fast or slow tempo? Clap the quarter note to find out. What do you think would be a suitable tempo text?

Adagio or Largo would both work well here. This is an extremely slow tempo.

Consider this overture by Gioachino Rossini (you may have heard it before):

https://www.youtube.com/watch?v=zFVyqtDB2M

IIl Barbiere di Siviglia Overture by Rossini, Excerpt: 1:30-2:00

Consider the excerpt from 1:30-2:00. What tempo marking would you expect to find?

Now consider the excerpt from 2:00-2:30. What sudden change happens in the music after the held chord? What tempo marking would you expect to find?

For the first excerpt, the melody in the winds can and then strings is of a relatively moderate tempo. A tempo marking such as andante or moderato should be expected.

For the second, the excerpt, the tempo picks up dramatically. A tempo marking such as allegro would be fitting of this new part of the piece.

What is a gradual tempo change?

Tempo changes aren't all immediate like in Rossini's overtures. The tempo of a piece of music can also speed up or slow down gradually.

If the music speeds up, this is called an accelerando. If it slows down gradually, this is called a ritardando. If it slows down abruptly, this is a ritenuto.

Let's see an example of each of these.

https://www.libertyparkmusic.com/common-tempo-markings/

In this example, we see that an accelerando can be abbreviated as "accel." and ritardando as "rit." The dashed line that comes after the accel. is option, though it shows the performer exactly when they should stop. Typically, a score will have an accel. lead to an immediate tempo change. This example, however, does not.

Let's hear these in music!

https://www.youtube.com/watch?v=_Kv5q2mrfDE

In the Hall of the Mountain King by Grieg

Listen to this entire piece. Now, listen to the first 10 seconds and the last 10 seconds. See how the form of the piece is simply one giant accelerando?

https://www.youtube.com/watch?v=Zh9dHyTxYkI

1812 Overture (Finale) by Tchaikovsky

Listen to the first 47 seconds of this work by Tchaikosvky. What would be an appropriate tempo marking?

Now listen from 0:47 to 1:30. What is happening here?

What would be a good tempo marking to describe the section that starts at 1:30?

The first excerpt is fast! An allegro or presto marking would suit it well. Then, a gradual ritardando happens between 0:47 and 1:30. Finally, it settles into a slower tempo. Andante would be a good pick for this one.

Tempo Rubato

One other important concept is tempo rubato, which literally translates to "robbed time."

Rubato is a style of playing which generally is represented by a general freedom with respect to tempo. You'll hear some notes played longer than they were written, and others are shorter. The works of Frederic Chopin are often considered the standard in rubato playing.

Take a listen to Chopin's Mazurka in A minor, Op. 17, No. 4 and see if you can tell how the performer plays it rubato:

https://www.youtube.com/watch?v=xW-Vb615l7Q