Trying Wilhelm Friedemann Bach to join his father's polyphonic art with the gallant, sensitive musical language of his time, eventually led to a "failure" at the highest level. Be as personal as idiosyncratic style was taken up by his contemporaries with incomprehension. To mature late works full set of technical sovereignty, formal audacity and depth of expression hide behind playfully easy elegance and musical discipline. The study of the oldest Bach son was definitely worth it!