[@Natsucooldude]
It seems there are a few boss monsters who are sound/music based.
*wants to be one too but lives in the woods and is understandable if noone knows them very well outside of their posting at the guard post* >_>
Also, Jack's combat isn't sound or music based, so I guess it doesn't matter that much. I only brought it up from the comment just now which made me curious to read into the other monsters.