Way, way back when I was making the original game I had my buddy, Lance, build the soundtrack. That sound file takes up between 1.5-2mb because it’s a bit long and high quality. In the course of testing, a couple people mentioned it would be nice if there were a different soundtrack on each chapter (every chapter is five levels). At the time that seemed outlandish given that would add at least 12-15mb more to the total game size.
Some full disclosure: I always turn off the music right away in any game. For the most part, they don’t interest me and don’t seem to add to the game as much as they subtract. But in this, I know I’m the minority. Music has very strong associations with experience and many people enjoy having it tailored into the ride.
After some considerable thought and a few more conversations with Lance, I decided to go ahead and hire him to do a different soundtrack per chapter. To my delight, these songs have been incredible. Per my point from above, I rarely enjoy video game music, yet I find myself enjoying it while testing over and over again. I’d call that a good sign.