Bach.
Is this is even a question?
Yes, which Bach? Sure, J.S. Bach is more famous but for example his sons played an important role in the history of music. W.A. Mozart once said something like: "Bach is the father, we are the sons." and in fact he was referring to C.P.E. Bach (the most famous of J.S. Bach's sons). J.C. Bach (another of Bach's sons) was an inspiration for W.A. Mozart's concerto style. W.A. Mozart discovered J.S. Bach later in life.
As for the thread topic, depends how musical hero is defined. In my case I've been wanting to compose and have in fact recently started composing some (nothing finished yet) and the music of alot of composers is inspiring. You could say I have lots of musical heroes but to mention a few: J.S. Bach, Antonio Vivaldi, G.F. Handel, G.P. Telemann, W.A. Mozart, Joseph Haydn, Ludwig van Beethoven, Franz Schubert, Frederick Chopin, Jean Sibelius, Carl Nielsen, Claude Debussy, Maurice Ravel, Henry Cowell, Leo Ornstein, Anton Bruckner, Erik Satie, Dmitri Shostakovich, John Barry, Tomohito Nishiura, Michael Giacchino... Basically I try to listen to lots of classical, film, TV and video game music.
