Contemporary players covering classic albums isn't always a sure-fire success. But Impulse! Nights, a weeklong celebration of the Impulse! label's 50th anniversary, is packed with events virtually guaranteed to satisfy. Up first, appropriately enough, is a performance of Africa/Brass, John Coltrane's uneven but thrilling label debut, presented in a stripped-down quintet arrangement by Ravi Coltrane, the saxophone icon's son, and fellow tenorist David Liebman.