I'm not the biggest rhythm game fan, but that being said I think you took this concept and executed it very well! Like Fritz said, there's room for some more juice and I can also see what Beauport is saying about being on beat, but for a jam and getting the core mechanics down, this is very good. I appreciate that the color of the room changes depending on what key you are holding, it made it much easier to see at a glance if I hitting the right key.