by Scott YanowThis double LP, which came out in 1975, contains two superior (and previously unissued) sessions featuring the great tenor saxophonist Sam Rivers. Actually, one of the dates was originally led by pianist Andrew Hill, who performs in a quartet with Rivers, bassist Walter Booker, and drummer J.C. Moses. While that set has six of Hill's provocative originals, the other album (which teams Rivers with altoist James Spaulding, trumpeter Donald Byrd, trombonist Julian Priester, bassist Cecil McBee, and drummer Steve Ellington) features six of the tenor saxophonist's compositions. These very adventurous performances (some of Blue Note's finest avant-garde dates) are often intense and always adventurous. This stimulating music ranks with Sam Rivers' most significant recordings.