Classical music, tango and cabaret. From Kurt Weill to Schoenberg, from Carlos Gardel to Britten, these musical genres have always found ways to meet.To celebrate the music of tango composer, Astor Piazzolla in the year that would have seen his 100th birthday, William Ludwig and Dean Austin, the cabaret kings (The Londonist) join forces with two of Londons most exciting classical musicians.