On its self-titled fourth album, Bio Ritmo's hard edge gleams like a razor. "El Monte" kicks things off with a bracing blast of brass and an inspired vocal from Alvarez. "El Rayito" is a slow, simmering bolero accented by the subtle, soulful piano work of Marlysse Simmons and Bob Miller's subdued trumpet, while "Jabula" is a jubilant descarga with synth swoops, a duck call solo, and spirited coros from Alvarez -- reminiscent of the Nuyorican dance hits of the late Sixties.