Fuentes took complete responsibility for the group's musical direction, and enriched the evolution that for many years had conserved the primitive and unstudied qualities of mariachi. The changing sound of the Mariachi Vargas de Tecalitlán was redirected without the abandonment of its roots or traditions. The Huapangos and Sones (which were two very distinctive styles of the mariachi music) were being interpreted in many diverse and different ways. The Mariachi Vargas recorded the Sones with arrangements and adaptations as patterns for other groups. This stratagem promoted the concept that all mariachi groups could be unified to those versions by taking them as examples. The traditional songs and the original sound of the mariachi began to mature in the 1950s. It was during the recordings of the "Golden Age of the Huapangos" that the compositions, arrangements and musical direction of Rubén Fuentes, and the unequaled voice of Miguel Aceves Mejía, initiated a musical shift that would change the sound and instrumentation of the mariachi.