A native of Guánica in the south west of Puerto Rico, Rogelio “Kito” Vélez began his career as a trumpet player in Mayagüez, where he participated briefly in the orchestra of Los Ases del Ritmo, before moving to San Juan at the start of the 1950s. There he joined the big band of César Concepción, who had been the first to arrange plena in that format. This was likely a decisive period in his development, which made him into the principal arranger of Cortijo’s combo in its golden age.
In 1962, Kito Vélez was one of the musicians who left Cortijo’s group due to Ismael Rivera’s arrest for drug possession to form a new group, El Gran Combo. As had been the case with Cortijo’s combo, Kito was responsible for all the arrangements for the first six albums by the Gran Combo but wasn’t its director as their pianist, Rafael Ithier, held the baton. He likewise freed himself from this combo to assemble his own orchestra in 1964, with which he recorded two LPs for Ansonia Records and another for Seeco.