A versatile bassist with a particular flair for the avant-garde, Mark Helias is also an underappreciated composer, and no slouch with a funk groove either. Helias was born in Brunswick, N.J., in 1950, and didn't begin playing bass until age 20; however, he wound up studying music at Yale, graduating in 1976. In 1977, he formed BassDrumBone with trombonist Ray Anderson and drummer Gerry Hemingway, and began appearing as a sideman on albums by the likes of Anthony Braxton, Dewey Redman, Barry Altschul, and Anthony Davis. In 1981, Helias co-founded the free funk ensemble Slickaph...