Introduced to many by Bob Dylan’s reference in Freewheelin’s “I Shall Be Free,” the late Babatunde Olatunji was a Nigerian-born master drummer, teacher and composer. From the late ‘50s until his death at age 75 last April, he recorded some of the best world music around, including his masterpiece Drums of Passion in 1959. The posthumous Healing Session is a tranquil collection of African meditations full of subtle percussive intricacies and hypnotic chants that take the listener on a musical journey through the dark continent of the mind and its undiscovered places.