Adaptive Audio: A Beginner's Guide to Making Sounds for Video Games
[01.27.09] - Dan Carter and Michael Worth
At first glance, sound design for film and television and sound design for video games seem to be very similar. Both aim to immerse audiences in their constructed worlds. Whether you're watching a Star Wars movie or playing a Star Wars game, the trademark whoosh of a T.I.E. fighter flying by instantly transports you into Star Wars' sci-fi realm. The audio in both film and video games also heightens and supports the emotional state and excitement of viewers and players. When the evil breathing of Darth Vader creeps into the soundscape, even if he's not on screen, a fantastic chill runs up our spines, because we know the Dark Side is afoot!
However, there are several ways in which audio for games is markedly different from that of film. First and most importantly, film sound design is temporally scripted down to the last floor squeak. When the director creates a scene, he knows exactly how many gunshots will have been fired in that scene, and when they occur. He also knows where in "space" those gunshots occurred (one back on the balcony, two off to the left, etc.). Because everything is predetermined, the sound effects team can script a perfect timeline of effects for each scene.
In video games, on the other hand, no one knows how many sound events are going to occur at any one point -- this is why audio for games is called "adaptive audio."
If a sound designer makes an absolutely humongous laser blast for his top-down shooting game, and the first thing the player does is mash the fire button as quickly as possible, then there may be 15 sudden "gunfire" events happening in three seconds... all from the player's gun alone! God forbid the player should decide to simultaneously activate and detonate 10 mines at the same time.
The difference between knowing the events of a sequence and not knowing them makes designing the audio of video games a much more tightly pre-visualized craft than doing it for film or television. It completely changes the strategies an audio designer uses to create sounds.
Also, because the narrative in a game is often driven by the player, sound effects often cue the player to an advancement in the story. For example, there will often be an ambience shift when a player moves from a regular area to a "mini-boss" area. Maybe the cries of the damned get louder, and the sound of chains and whips enter the ambiance. In that respect, a sound designer is actually helping to convey the story of the game, alerting the player to a different chapter in the game.
Finally, sound design helps the player quickly identify state changes, especially in casual games. A classic example is the mushroom power-up sound in Super Mario Bros. As the player is often focused on looking ahead, the sound cue that he has picked up a power-up is often all he needs to know that his game state has changed.
Newcomers to game audio development should keep these strategies in mind as they start designing sounds. They need to be aware of how their sound designs will support the emotional state of the gameplay, and how it will help to create the "world reality" of the game as it's being played. At the same time, it's important to be aware of the non-linear, non-narrative aspects of game sound effects, and how the sound design will work to enhance the gameplay of the game, which does not necessarily fall into a linear timeline.
Audio Gets Organized
When creating sound effects, knowing how to organize the work -- and knowing exactly what to track -- can easily make the difference between a successful, creative, and compelling outcome, and a failed project.
Audio designers absolutely need to record and track each version of their sound effects: when they were submitted, when they were reviewed, and what feedback the client or game development team had about them.
For smaller games, a simple Google Documents spreadsheet will suffice. But for larger projects, audio designers typically use a database or project management application like Basecamp to track which effects have been done, and what stage of the pipeline they are in.
A word of advice: Back up everything! We have two external hard drives, and we back up my project folder to both of them each day. Our team even intentionally uses two different brands of hard drive. You can never be too careful.
Having a consistent naming convention for all audio files is another critical way audio designers keep their work organized, and therefore usable. (We'll discuss naming conventions in more detail in the Pre-Production section.)