I built a drum loop of 4bars in 130bpm and 4/4. Then I used a D-Major scale for every other instrument. The loops loosely fit together. In our game you hear one 'cacophony' of 3 or more instruments and get presented about twice as much. You have to select which instruments you heared.

https://www.youtube.com/watch?v=XK5joZ-7_Jo