Argentinian Tango-Fusion band funded 1955, as an evolution of Piazzolla's string ensemble. Formed with the objective of introducing jazz-influenced free improvisation to Tango aesthetics.
Considered the to have coined Tango Nuevo as a genre.

Formation:
Bandoneon & Direction: Astor Piazzolla
Bandoneon: Leopoldo Federico
Violin: Enrique Mario Francini / Hugo Baralis
Contrabass: Juan José Vasallo
Cello: José Bragato
Piano: Atilio Stampone
Electric Guitar: Horacio Malvicino

Piazzolla released two albums with this formation: Tango Progresivo (Argentina, 1956) and Tango Moderno (Argentina, 1957)
Disbanded in 1958, product of frustrations over financial difficulties.