The Infernal Tune

It was said that Beethoven composed a melody so powerful, it could summon The Devil.
He never wrote it down, and never played it with anyone nearby.
Except his nephew Karl.
Perhaps this is why he fought to keep custody of Karl, to prevent him from revealing this secret?
Or maybe Karl attempted suicide after seeing his uncle plead with The Prince Of Darkness for his hearing back?
His doctor prescribed treatments containing lead to block out the infernal influences, sending the composer into painful and confusing fits.
Karl whispers, “The piano is out of tune. Does Satan listen now?”