I'm a sucker for games about music (heck, my last jam game had music-making as a major feature), I loved this. The aesthetic here is tight, and really well put together. The difficulty felt like it was right about the right level. I was kind of reminded of Magicka, which is great. Not sure if that was intentional.
My only notes are pretty minor ones:
- I wish the music notes played on key down instead of playing every frame while held: the samples are lovely, but become kind of messy if you hold a key a touch long
- As someone without a numpad on any of my available keyboards, I had to do some kind of awkward contortions to play melodies, and never really managed to do it well while also moving around. Not sure what, if anything you could do to alleviate that? Customizable controls maybe, but that's too much to ask for a jam game haha.
- I'm not sure if it's a bug, but it seemed moving around changed what song I had highlighted in the UI? Super minor, but if you're considering expanding this out into a larger game, it's something that might be worth looking into.