<P> Although some modernist music is also avant - garde, a distinction can be made between the two categories . According to scholar Larry Sitsky, because the purpose of avant - garde music is necessarily political, social, and cultural critique, so that it challenges social and artistic values by provoking or goading audiences, composers such as Igor Stravinsky, Richard Strauss, Arnold Schoenberg, Anton Webern, George Antheil and Claude Debussy may reasonably be considered to have been avant - gardists in their early works (which were understood as provocative, whether or not the composers intended them that way), but the label is not considered appropriate for their later music . For example, modernists of the post--World War II period, such as Milton Babbitt, Luciano Berio, Elliott Carter, György Ligeti, and Witold Lutosławski, never conceived their music for the purpose of goading an audience and cannot, therefore, be classified as avant - garde . Composers such as John Cage and Harry Partch, on the contrary, remained avant - gardists throughout their creative careers . </P> <P> Popular music, by definition, is designed for mass appeal . The 1960s saw a wave of avant - garde experimentation in popular jazz, represented by artists such as Ornette Coleman, Sun Ra, Albert Ayler, Archie Shepp, John Coltrane and Miles Davis . In the rock music of the 1970s, the "art" descriptor was generally understood to mean "aggressively avant - garde" or "pretentiously progressive". Post-punk artists from the late 1970s rejected traditional rock sensibilities in favor of an avant - garde aesthetic . In 1988 the writer Greg Tate described hip hop music as "the only avant - garde around, still delivering the shock of the new ." </P>

A avant-garde style of music based on repetition is called