Cruise Elroy

Music and sound in Portal 2

June 20, 2011

Do you remember recommending Portal to your friends, or having it recommended to you? There was this little dance where you had to temper your enthusiasm to avoid overselling what was, ostensibly, a puzzle game. “No, no, I mean, it’s really cool — it’s like, you make these two holes, and you go in one, and then…listen, you just have to play it, okay?” The fact that Portal could be spoiled was, itself, a spoiler.

From that perspective, Portal 2 was at a disadvantage from the start. Valve had already played their plot twist card, their novel mechanic card, and their Jonathan Coulton epilogue card; while continuing along those lines seemed like a safe bet, I wasn’t sure if bouncy gel and the like would be enough to support several more hours’ worth of test chambers. At the time I expressed this doubt by asking if Portal “needed” a sequel, though that framing seems odd in retrospect.

Regardless, my fears were unfounded. Portal 2 doesn’t — and, indeed, couldn’t — recreate the tremendous effect of its predecessor, but it’s still fresh and funny and stunningly executed. For more on that I refer you to Mitch Krpata, Kirk Hamilton, Michael Abbott, and Matthew Burns, all of whom wrote wonderfully thoughtful pieces while I was dicking around for two months.

So instead of rehashing those posts further, I thought I would talk a little about music and sound.

From Geoff Keighley’s must-read feature “The Final Hours of Portal 2”:

The first Portal was renowned for its musical ending, and in Portal 2 composer Mike Morasky wanted to up the ante with interactive music that would subtly evolve as players completed a puzzle. Run along orange speed paint and the music speeds up. Successfully jump across a ledge and the music shifts to let you know you’re doing a good job. “The puzzles are thanking you for playing with them,” is how Morasky puts it. “They love you.”

Interactive music isn’t new, of course, but I haven’t seen anything quite like Portal 2’s approach before. Sound and music are more thoroughly interwoven, and the distinction between the two is less meaningful.

Film editor and sound designer Walter Murch has a theory about categorizing sound. Using the spectrum of visible light as an analogy, he imagines an aural spectrum with “encoded” sound at one end and “embodied” sound at the other:

When you think about it, every language is basically a code, with its own particular set of rules. You have to understand those rules in order to break open the husk of language and extract whatever meaning is inside. Just because we usually do this automatically, without realizing it, doesn’t mean it isn’t happening. It happens every time someone speaks to you: the meaning of what they are saying is encoded in the words they use. Sound, in this case, is acting simply as a vehicle with which to deliver the code.

Music, however, is completely different: it is sound experienced directly, without any code intervening between you and it. Naked. Whatever meaning there is in a piece of music is ‘embodied’ in the sound itself. This is why music is sometimes called the Universal Language.

What lies between these outer limits? Just as every audible sound falls somewhere between the lower and upper limits of 20 and 20,000 cycles, so all sounds will be found somewhere on this conceptual spectrum from speech to music.

Most sound effects, for instance, fall mid-way: like ‘sound-centaurs,’ they are half language, half music. Since a sound effect usually refers to something specific – the steam engine of a train, the knocking at a door, the chirping of birds, the firing of a gun – it is not as ‘pure’ a sound as music. But on the other hand, the language of sound effects, if I may call it that, is more universally and immediately understood than any spoken language.

What Portal 2 does, I think, is push sound effects and music towards each other so that they meet somewhere in the orange on Murch’s spectrum.

Let’s listen: