Coming to you straight from the soulful, unpolished heart of Zanzibar, you hear the sweaty sound of unison violins and voices-a male lead singer’s entreaties answered by female chorus-over the steady pulse of drums. On Kidumbak Kalcha, Ng’ambo-the Other Side of Zanzibar (Dizim 4501; 70:25), the music represents one of those special island traditions, honed with a distinctive manner in this Indian Ocean outpost. Kidumbak, common at weddings, is a dance-inductive music with an often openly sensuous content, in contrast to the more subdued taarab style indigenous here. Ng’ambo is the poor sector, off to the side of Stone Town, where the music gains that raw, soulful intensity often found in less-gentrified neighborhoods around the globe. This is one of those musical artifacts, on the Afro-Arabic axis, that pulls you into another world.