Stephen Michael Reich (born October 3, 1936) is an American composer who pioneered the style of minimalism. His innovations include using tape loops to create phasing patterns (examples are his early compositions, It's Gonna Rain and Come Out), and the use of simple, audible processes to explore musical concepts (for instance, Pendulum Music and Four Organs). These compositions, marked by their use of repetitive figures, slow harmonic rhythm and canons, have significantly influenced contemporary music, especially in the US. Reich's work took on a darker character in the 1980s with the introduction of historical themes as well as themes from his Jewish heritage. The Guardian has described Reich as one of the few composers to have "altered the direction of musical history," has been called "America's greatest living composer" (the Village Voice) as well as "...among the great composers of the century" (New York Times).[citation needed] Reich's style of composition has influenced many other composers and musical groups, including Philip Glass (especially his early pieces), John Adams, the progressive rock band King Crimson, and the art-pop and electronic musician Brian Eno. On January 25, 2007, Reich was named the 2007 recipient of the Polar Music Prize, together with Sonny Rollins.