Of his musical generation — roughly the ’60s and ’70s — Puerto Rico’s Rivera was the finest non-Cuban singer of all, and perhaps the finest without restriction. His improvising brilliance was enhanced by a deep, heavy voice of a type rare in Latin singing. He and percussionist/bandleader Cortijo were major influences in NYC proto-salsa through their superb recordings of Puerto Rican bombas and plenas. Unfortunately an extended sabbatical at the federal government’s expense interrupted his career at a critical moment, but those who know, know just how good he was. – John Storm Roberts