Other Violets (Not Two), the superb new album by the Chicago freebop quartet Engines, is a collaboration with the great Danish reedist John Tchicai (who died last October at the age of 76), and whenever I hear something by him I usually think of one of my all-time favorite pieces of music, one that he had an important hand in creating. Witchdoctor’s Son (Steeplechase) is a 1978 album by the brilliant South African bassist Johnny Dyani, and while the entire record is superb, the extended performance on “Magwaza,” the leader’s adaptation of a traditional folk song, can’t help but tower over every other track. The piece is built around a warm, hypnotic ostinato bass pattern (which he perpetually tweaks with subtle rhythmic displacements and harmonic substitutions) and a spindly acoustic guitar arpeggio delivered by Alfred Nascimento, but the real heart of the piece is the stunning improvisations by Tchicai and fellow reedist Dudu Pukwana (another South African expat who, relocated to England in the mid-60s with Dyani and the rest of the members of the Blue Notes). They prod, collide, and caress each other’s lines in one of the most sublimely locked-in, empathetic, and utterly gorgeous passages I’ve ever heard. I can’t imagine how many times I’ve listened to it since I first heard it in the late 80s, when Don Meckley played it while DJing at the long-gone bar Lower Links, but I don’t think I’ll ever tire of it.