Fez's proprietary music system was developed by Renaud Bedard, with plenty of input from myself and others. This robust tool allowed us to treat the music in Fez modularly, writing multiple versions of tracks, often split into individual elements, to be played at different times of day (in-game), and in different levels. The music system also handles loop playback on an element to element basis, using tempo and bar counting. This allowed us to write songs made up of elements of different bar lengths, and give them their own unique instructions to create music that will evolve on its own. We also used the system to tie pickup SFX into the musical palette, by specifying which note scales to use for pickup SFX depending on which song was playing.
ZONR features audio treatment that is specifically designed to last the 90 seconds that gameplay always lasts. The music evolves and builds in tension over the course of those 90 seconds, in an effort to emphasize the gameplay. In addition, musical tones are used as sound effects to help create an engaging musical experience. These tones are intelligently sequenced and kept in sets, which are called based on which period of time the player is currently experiencing. This ensures that the tones played are always harmonious with the music.