Díaz was born in San Juan, Puerto Rico, the capital of the island, but lived and was raised in the town of Cataño. He attended Robinson Elementary School where, at the age of 8, he started to participate in the school's activities as a singer. In his first school play, when he was 10 years old, he sang the song "Old Black Joe", which became his favorite. After finishing his primary education, Díaz attended the University of Puerto Rico High School in Río Piedras. While in high school, he took singing classes and participated in various presentations around the island.