But actually imagine this.
Being a music student at Hogwarts. I bet the room of requirement would turn into a great place to have completely sound proof and flawless acoustics for a bunch of practice rooms. And I bet Hogwarts would have steinways and good mirrors should you want to check your physical technique. Great instruments for use to practice secondary as well as the best private instructors. And the library would probably have every score and libretto known to man.