Subject (music) facts for kids

In music, a subject or theme is a main musical idea. It's usually a tune or melody that a whole piece of music is built from. Think of it as the main character of a song.

What Makes a Musical Theme?

A musical theme is a complete musical idea. It's longer than a small musical motif or idea. A theme is often a full musical phrase or section. It can sound complete even when heard by itself. Composers often change and develop these themes. This helps to give the music its structure.

Themes in Different Music Styles

Music can be built in different ways using themes.

• Monothematic music uses only one main theme.
• Polythematic music uses several different themes.

Most fugues are monothematic. This means they focus on just one main subject. Most pieces written in sonata form are polythematic. They use a few different themes.

In a fugue, the main theme is called the 'subject'. It is introduced by one musical voice. Then, other voices repeat the subject. Sometimes they repeat it at a different pitch.

Some pieces have a main subject. Then, a second melody might appear. This second melody is sometimes called a 'countersubject' or 'secondary theme'. In sonata form, a section might have several themes. These are sometimes grouped together. This is called a 'theme group' or 'subject group'.

Music Without Clear Themes

Some music does not have clear, repeating themes. This is called 'athematic' music. It means "without a theme." Early works by composers like Arnold Schoenberg and Anton Webern sometimes used this style. An example is Schoenberg's Erwartung. Later composers also explored this idea.

What is a Countersubject?

In a fugue, a countersubject is another important melody. It plays at the same time as the main subject. When the first voice finishes playing the subject, a second voice starts the subject. At this point, the first voice often begins playing the countersubject. The countersubject usually sounds different from the main subject. It creates a nice contrast.

A countersubject is a continuing melody. It is played by the voice that started with the subject. It plays against the 'answer' (which is the subject played by another voice). Countersubjects are often designed to work well both above and below the main subject.

Here's a simple idea of how a fugue might start: Soprano voice: Answer Alto voice: Subject Countersubject

See also

In Spanish: Tema (música) para niños

• Attacco
• Cell
• Figure
• Formula composition
• Leitmotif
• Thematic transformation