Arolas first learned to play the guitar before learning the bandoneon which became his instrument of choice. His nickname was El Tigre del bandoneón (the tiger of the bandoneon).
Arolas is regarded as one of the early masters that helped to define the future of tango music in Argentina. He was avant-garde in his composition and often utilised unconventional instruments such as the saxophone violoncello and the banjo.
His most famous works include Lágrimas, La cachila, El Marne and Viborita.