These sessions, mostly recorded in 1969 and 1970, extend the jazz-rock experiment Miles Davis first brought to fruition in Bitches Brew in August 1969. Gone are the Broadway standards of the mid 50s, the modal jazz of the late 50s and the free-bop of the 60s, replaced by protracted vamps on slender themes and simple bass riffs. Looking for his slice of the rock cake, Davis had adopted the sounds of contemporary pop, adding sitar and exotic percussion to his line-up and putting increased emphasis on electric instruments. Temperamentally speaking, these long, moody pieces aren't that far from the melancholy haze of his 1960 Sketches Of Spain, but they develop mostly by small variations in texture and take a long while coming to the point. The 1969-70 band was still full of jazz talent though, and along the way there are good solos from Chick Corea and Steve Grossman. --Mark Gilbert