Music of the 20th Century

The Age of Musical Diversity

Composer Elliot Carter with head on hand at his piano.
20th-Century composer Elliot Carter.

Cheryl Chenet / Getty Images

The 20th century is described as the “age of musical diversity” because composers had more creative freedom. Composers were more willing to experiment with new music forms or reinvent music forms of the past. They also took advantage of the resources and technology that were available to them. 

New Sounds of the 20th Century

By closely listening to the music of the 20th century, we can hear these innovative changes. There is, for example, the prominence of percussion instruments, and at times the use of noisemakers. For example, Edgar Varese’s "Ionisation" was written for percussion, piano, and two sirens.

New ways of combining chords and building chord structures were also used. For example, Arnold Schoenberg’s Piano Suite, Opus 25 used a 12-tone series. Even the meter, rhythm,​ and melody became unpredictable. For example, in Elliott Carter’s “Fantasy,” he used metric modulation (or tempo modulation), a method of seamlessly changing tempos. Music of the 20th century was quite different than the music of previous periods.

Musical Concepts That Defined the Era

These were some of the most important musical techniques used by 20th-century composers.

  • Emancipation of dissonance – Refers to how freely 20th-century composers treated dissonant chords. What was considered dissonant by past composers was treated differently by 20th-century composers.
  • Fourth chord – A technique used by 20th-century composers in which tones of a chord are a fourth apart.
  • Polychord – A compositional technique used in the 20th century wherein two chords are combined and sounded simultaneously.
  • Tone cluster – Another technique used during the 20th century wherein tones of a chord are either a half step or whole step apart.

Comparing the 20th Century Music to Past Eras

Although 20th-century composers used and/or were influenced by composers and music forms of the past, they created their own unique sound. This unique sound has many different layers to it, coming from the combination of instruments, noisemakers, and shifts in dynamics, meter, pitch, etc. This differs from the music of the past.

During the Middle Ages, the musical texture was monophonic. Sacred vocal music such as Gregorian chants were set to Latin text and sung unaccompanied. Later on, church choirs added one or more melodic lines to the Gregorian chants. This created polyphonic texture. During the Renaissance, the size of church choirs grew, and with it, more voice parts were added. Polyphony was widely used during this period, but soon, music also became homophonic. Musical texture during the Baroque period was also polyphonic and/or homophonic. With the addition of instruments and the development of certain musical techniques (ex. basso continuo), music during the Baroque period became more intriguing. Musical texture of Classical music is mostly homophonic but flexible. During the Romantic period, some forms used during the Classical period were continued but was made more subjective. All of the various changes that happened to music from the Middle Ages to the Romantic period contributed to the music of the 20th century.

20th Century Musical Instruments

There were many innovations that happened during the 20th century that contributed to how music was composed and performed. The United States and non-Western cultures became influential. Composers also found inspiration from other music genres (i.e. pop) as well as other continents (i.e. Asia). There was also a revival of interest in the music and composers of the past.

Existing technologies were improved upon and new inventions were made, such as audio tapes and computers. Certain compositional techniques and rules were either altered or rejected. Composers had more creative freedom. Musical themes that weren’t widely used in past periods were given a voice.

During this period, the percussion section grew and instruments that weren’t used before were utilized by composers. Noisemakers were added, making the tone color of 20th-century music richer and more interesting. Harmonies became more dissonant and new chord structures were used. Composers were less interested in tonality; others completely discarded it. Rhythms were expanded and melodies had wider leaps, making music unpredictable.

Innovations and Changes During the 20th Century

There were many innovations during the 20th century that contributed to how music was created, shared and appreciated. Technological advancements in radio, TV, and recording enabled the public to listen to music in the comforts of their own home. At first, listeners favored the music of the past, such as Classical music. Later on, as more composers used new techniques in composing and technology allowed these works to reach more people, the public grew interested in new music. Composers still wore many hats; they were conductors, performers, teachers, etc.

Diversity in 20th Century Music

The 20th century also saw the rise of composers from various parts of the globe, such as Latin America. This period also saw the rise of many women composers. Of course, there were still existing social and political problems during this period. For example, African-American musicians weren’t allowed to perform with or conduct prominent orchestras at first. Also, many composers were creatively stifled during the rise of Hitler. Some of them stayed but were forced to write music conforming to the regime. Others chose to migrate to the United States, making it a center of musical activity. Many schools and universities were founded during this time that catered to those who wanted to pursue music.