After Mariachi Coculense’s extended engagement at the 1933-34 Chicago World’s Fair, José Marmolejo (nephew of Cirilo) left his uncle’s mariachi to form a group of younger musicians with more modern ideas. The most novel feature of this new ensemble was that it contained a trumpet, a controversial addition any mariachi in those days. Radio, films, and records soon helped Mariachi Tapatío become the most popular mariachi in Mexico — and the trumpet to become a permanent feature in mariachi music.