Description
20th century classical music was extremely diverse, ranging from the late Romantic style of Sergei Rachmaninoff to the complete serialism of Pierre Boulez, and from the simple triadic harmonies of minimalist composers such as Philip Glass to the musique concrète of Pierre Schaeffer and the microtonal music adopted by Harry Partch, Alois Haba and others.

Among the most prominent composers of the 20th century were Gustav Mahler, Richard Strauss, Giacomo Puccini, Claude Debussy, Arnold Schoenberg, Sergei Rachmaninoff, Igor Stravinsky, Dmitri Shostakovich, Benjamin Britten and Aaron Copland. Classical music also had an intense cross fertilization with Jazz, with several composers being able to work in both genres, including George Gershwin. An important feature of 20th century concert music is the existence of the splitting of the audience into traditional and avant-garde, with many figures prominent in one world considered minor or unacceptable in the other. Composers such as Anton von Webern, Elliot Carter, Edgar Varese, Milton Babbitt, Luciano Berio have devoted followings within the avant-garde, but are often attacked outside of it. As time has passed, however, it is increasingly accepted, though by no means universally so, that the boundaries are more porous than the many polemics would have you believe: many of the techniques pioneered by the above composers show up in popular music by The Beatles, Pink Floyd, Mike Oldfield, Nirvana and in film scores that draw mass audiences.

It should be kept in mind that this article presents an overview of 20th century classical music and many of the composers listed under the following trends and movements may not identify exclusively as such and may be considered as participating in different movements. For instance, Igor Stravinsky may be considered a romantic, modernist, neoclassicist, and a serialist.

The 20th Century was also an age where recording and broadcast changed the economics and social relationships inherent in music. An individual in the 19th century made most music themselves, or attended performances. An individual in the industrialized world had access to radio, television, phonograph and later digital music such as the CD.
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