Oh God, dynamicly Layerd Music.

Zitat Zitat
There is an epic sense of drama in Portal 2 which is complimented by some cinematic underscore that would not have been appropriate in the first Portal, and while we very consciously maintained a certain homage to the ambient nature of the music in Portal, Portal 2 has much more variety in terms of styles and presentation of its music.
Zitat Zitat
There are several cases where the music adds channels and complexity as you successfully solve portions of the puzzle, with each additional piece of music actually coming from the device that is participating in the activated game play mechanic. Obviously, this can heighten the sense of achievement as one completes the puzzle but also turns the mechanics of the puzzle into a sort of interactive music instrument that you can explore by selectively triggering the different channels of music with differing timings and configurations. Most of the interactive music is also positional so that as you move through the space you also change the mix and volume of the music you are hearing, which invites explorations of the space as well.
Dat Halls of Science Sample.