Music" has never been recorded by Reich himself, but was introduced to rock audiences by Sonic Youth in the late 1990s. Reich also tried to create the phasing effect in a piece "that would need no instrument beyond the human body". He found that the idea of phasing was inappropriate for the simple ways he was experimenting to make sound. Instead, he composed Clapping Music (1972), in which the players do not phase in and out with each other, but instead one performer keeps one line of a 12-eighth-note-long (12-quaver-long) phrase and the other performer shifts by one eighth note beat every 12 bars, until both performers are back in unison 144 bars later. The 1967 prototype piece Slow Motion Sound was not performed although Chris Hughes performed it 27 years later as Slow Motion Blackbird on his Reich-influenced 1994 album Shift. It introduced the idea of slowing down a recorded sound until many times its original length without changing pitch or timbre, which Reich applied to Four Organs (1970), which deals specifically with augmentation. The piece has maracas playing a fast eighth note pulse, while the four organs stress certain eighth notes using an 11th chord. This work therefore dealt with repetition and subtle rhythmic change. In contrast to Reich's typical cyclical structure, Four Organs is unique among his work in using a linear structure—the superficially similar Phase Patterns, also for four organs but without maracas, is (as the name suggests) a cyclical phase piece similar to others composed during the period. Four Organs was performed as part of a Boston Symphony Orchestra program, and was Reich's first composition to be performed in a large traditional setting. 1970s In 1970, Reich embarked on a five-week trip to study music in Ghana, during which he learned from the master drummer Gideon Alorwoyie. Reich also studied Balinese gamelan in Seattle in 1973 and 1974. From his African experience, as well as A. M. Jones's Studies in African Music about the music of the Ewe people, Reich drew inspiration for his 90-minute piece Drumming, which he composed shortly after his return. Composed for a nine-piece percussion ensemble with female voices and piccolo, Drumming marked the beginning of a new stage in his career, for around this time he formed his ensemble, Steve Reich and Musicians, and increasingly concentrated on composition and performance with them. Steve Reich and Musicians, which was to be