One of his closest friends from his days in the barrio was Chano Pozo, and in his singing style he has been called "as black a white guy as you would meet in Havana".

Valdés began his musical career in the Sexteto Habanero Infantil, where he played, variously, the guitar, tres, double bass, timbal and sometimes sang.

In June 1937 Valdés and Casino de la Playa began recording for RCA-Victor, making their debut with Bruca maniguá, a song composed by Arsenio Rodríguez.

In 1940, Valdés briefly joined the Orquesta Riverside (another of the big Cuban bands) before emigrating to New York City, which became his home base for the rest of his career.

In New York City he worked for Orquesta Siboney de Alberto Iznaga, Xavier Cugat, Noro Morales, Tito Rodríguez and Machito.

In 1947, Valdés and his Orchestra played at the third Cavalcade of Jazz concert held at Wrigley Field in Los Angeles which was produced by Leon Hefflin, Sr. on September 7.

Other performers were Woody Herman, The Blenders, T-Bone Walker, Slim Gaillard, The Honeydrippers, Johnny Otis and his Orchestra, Toni Harper, Sarah Vaughn, and the Three Blazers.

Numbers he composed include "Mondongo", "Rumba rumbero", "Loco de amor", "Los tambores", "Oh, mi tambó", "Bongó", "Dolor cobarde".