"Cantor de orquesta" is one of the characteristics of the Golden Age of tango (1935-55) .  Singers were integrated as a part of the orchestra, and many songs were written where poetry's importance was increased. There were many famous dupla (duos) - orchestra / star singer such as Tanturi-Castillo, D'Agostino-Vargas, Troilo-Fiorentino. Season 1 of  Bailongo De Los Domingos features a dupla for each episode.

Can you tell who they are in the photos below?