The violin-accordion Duo ViA! (Sinn Yang and Harald Oeler) made their debut in 2009 with the program Seasons at the Heidelberg Spring Festival. + At that time, it required a great deal of courage to present to the public, in a sold-out hall, one of the most popular and most frequently played classical works, Vivaldi’s I quattro stagioni in combination with Astor Piazzolla’s Las cuatro portenas. + For the Duo, the program Seasons was and still is both an experiment and a daring feat.