Fans of Lambert, Hendricks & Ross specifically, and vocal jazz in general, have long heard about the early sides recorded before the trio came together in 1957. In fact, each member -- Dave Lambert, Jon Hendricks, and Annie Ross -- was separately a pioneer in bop-inspired vocal improvisation, the type of vocalizing that concentrated on the most purely musical aspects of singing. The El Records compilation, Improvisations for the Human Voice, compiles 25 of those early sides and provides a terrific complement to their best recordings, the string of LPs they recorded for Columbia between 1959 and 1962 (which were collected on an excellent two-CD compilation, The Hottest New Group in Jazz). These tracks comprise a wealth of seminal vocal sides by the most inventive minds in the art of vocalese.