Yeah.
Your instruments are summoned, physical objects - like Sailor Moon's tiara. It's magical, it only shows up when she's transformed, but it's not the source of her powers. I have a loose idea of the magic system in this world, but uh... don't think too hard about it, okay? Otherwise you'll see the gaping plot holes that I've hidden behind cheap drywall.
Could you say it's like programming? Like, mortals can't comprehend magic in its entirety, and spellcasting is a means of directing magic without exposing yourself to it and getting your brain melted. Music happens to be the lowest-level programming language, so the mechanics behind the henshin give the characters musical instruments to channel their magic with for the most versatility without causing brain damage.
Overthinking is my burden.
SP3CT3R
Instead, think about a world where all the birds have been chased out of the city because they won't stop singing! An evil queen who has literally jailed whales for their songs! To tap a rhythm with spoons is illegal, and mothers can be charged with disturbing the peace if their children cry longer than five seconds, because they might accidentally produce a melody!
Our ideas can coexist. Consider an evil queen whose only weakness is a spell that can only be cast through music, and bans anything capable of producing a melody so that they don't accidentally cast it.
This is loterally the plot of an Ace Attorney case. Well, not quite but he does defend a whale (okay, it's an Orca same difference).
Valid.
We probably didn't give the RP enough funding on Kickstarter.
