The writing, voice acting, and audio design are great, they really set the atmosphere and pulled me into the story! The gameplay is not as interesting and well-developed as the other aspects, but I know in a game jam you have to stay simple to finish in time. Hopefully after the jam you can add more variety and complexity to the quests, and more opportunity to use the instruments to solve puzzles or challenge mini-bosses. Overall very well done, and kudos for using real voice actors!
By the way, the gamepad controls mostly worked for me in the browser, using Firefox on Windows with a Logitech F310 gamepad. The only things that didn't work were the LT and RT controls, nothing happened when I pressed them, so I had to use the keyboard to play instruments 3 and 4. (Update: The LT and RT controls worked correctly with the Windows download.) It's not a big deal, I only mention it in case it helps you debug. :)