Carl Philipp Emanuel Bach ( March 8 , 1714 â `` December 14 , 1788 ) was a German musician and composer . He was the second of the five sons of Johann Sebastian Bach and Maria Barbara Bach . Carl Philipp Emanuel Bach ( 8 March 1714 -- 14 December 1788 ) was a German Classical period musician and composer , the second of three sons of Johann Sebastian Bach and Maria Barbara Bach .