Real name: Guillermo Alfonso Bascuñán Dockendorff

Chilean musician and composer. He joined Los Cuatro Cuartos in 1963 with Pedro Messone and Luis Chino Urquidi, and later Los Solitarios (1967). In the first 70s he founded América Joven joining folk and rock instruments. With this band he toured to Spain where they even played with Joan Manuel Serrat, and he settled there for a long time, returning to Chile in 1976. He rejoined Los Cuatro Cuartos, being his musical director until 1980.