[In the first installment of a new series, journalist Tristan Donovan dives into a discipline-specific topic to discover the most important tips and techniques those who practice it can share. In this article, he tackles audio.]

Sound is crucial to any game, but what do you really have to concentrate on to reach the heights of the video game medium? Gamasutra caught up with audio directors to pick their brains for 10 juicy morsels of sound advice and ideas.

1. Focus on Sounds That Matter

"One of our mantras during the development of Saints Row: The Third was 'is this sound going to be meaningful to the player?'," says Ariel Gross, audio director at the THQ-owned studio Volition.

"Some sounds just need to be there and sound right. If you hit a dumpster, then it needs to sound close to a dumpster, but is that sound meaningful to the player? Usually not. They just need to be there. So we spent less time on object impact sounds than the unique sounds for the big moments in the missions.

"We had to keep asking ourselves 'How important is this sound?' and 'Would the player care?' If they did, we would put our time, money and resources towards that sound, but if the answer was 'Well, yeah, it's kinda important' or 'Not really', then we would spend a lot less time designing those sounds."

2. Blur the Boundary Between Sound Effects and Music

Martin Stig Andersen drew on the concept of electroacoustic composition when creating the audio for Playdead's Limbo. "My background is in electroacoustic composition, where instead of writing scores for orchestras you record sounds and then make a sound montage or collage that would become a piece of music," he says. "To do this I use the same tools as sound designers but I think of my work in a more musical, compositional way."

Limbo

The moment in Limbo when the boy nears the spider is a good example of how this works, he says. "Instead of putting in traditional music, I used sounds from the environment to create the same effect. So when you approach the spider, the wind sounds stand still, because that gives a tense feeling equal in suspense to using an instrument like a violin. But instead of having this abstract orchestra sound dropped in, I work with the sounds from the actual game space."

3. Be a Good Housekeeper

"Maintaining your library of sounds is not the sexy part of the job but it is one of the most important, and it's one of the places where you can fall down the worst," says Jeff MacPherson, the audio director of EA's FIFA games.

"When I work with or hire people, one of the things I value most is good housekeeping skills. If you cannot manage a database of 50,000 samples, you may make a mistake that could result in a lot of bad things happening. Something that is not licensed could make it into the game, so you could get sued, or bad content like swearwords get in, and you get into trouble with the ratings board.

"You could also lose stuff or not put the right stuff in. We're paying a lot of money to get a lot of different audio content, and so if you don't manage it properly in the databases and backup systems, you could get into trouble, and there's really no excuse."

4. Big Worlds Need Small Sounds

Open world games rely on streaming sounds more than most titles, so keeping audio file sizes down is important, says Volition's Gross.

"If the player is driving a car so the environment's streaming, and we try to call a sound because he starts shooting out of the window at 100 mph, we have to make sure those sounds get streamed off the disc at the same time as the world," he says. "So we make our sounds as small as possible."

But profiling the audio early is critical. "You need to profile constantly and as early as possible using DVD emulation on the 360 and actual Blu-ray disc on the PS3, rather than an installed copy of the game," he says.

"With Saints Row: The Third we found out frighteningly late that when we started playing on DVD emulation and Blu-rays that most of our sounds weren't even playing. We had to go back and optimize all our sounds, get rid of extra variations, and compress them further. It was a nightmare."

5. Sounds Should Serve Game Design

PopCap's sonic approach is to have sound effects that support the game's design, says the company's audio director Guy Whitmore. "The sound is always communicating something specific to the player that's very important to how you play the game," he says.

One example is how musical notes are used to signal progress in its recent Facebook game Solitaire Blitz, says PopCap's audio producer Becky Allen. "In the game multipliers are given for 10-card runs. When the player plays the seventh card in a row without interruption, a note on the glockenspiel is played. A different note is then played on the eighth card, then another different note on the ninth, creating a small three-note melody that plays well with the music. This progression of glockenspiel tones informs the player that they are progressing and on the right path."

6. Explore the Psychology of Sound

What we hear is not just a product of sound waves, but also of our state of mind, says freelance sound designer Alistair Lindsay, whose credits include Kinectimals and Defcon. "You might have big explosions for your game, but do they reflect how you would feel if you were a solider in the battlefield?" he asks.

"I've spoken to soldiers who've been in combat, and one guy said that your buddy can be right next to you firing his weapon, and it sounds like it's 200 yards away -- whereas the guy shooting at you sounds like he's right next to your head. Sound doesn't necessarily run on railroad tracks; it's not two plus two, it's two plus two plus perception."

Lindsay is hoping to take advantage of people's sonic perceptions with his work on Introversion's forthcoming jail boss sim Prison Architect. One simple example from that game is having the sound of a pistol being cocked will be played at a key moment in a cutscene involving a gruesome murder.

"That same sound effect is then used out of context in a later cutscene, the idea being that the dissonance between what the eye sees and the ear hears at that moment might re-trigger any emotion felt during the first gruesome scene. That idea has its root in neurolinguistic programming techniques," he says.

7. Peer Review Unfinished Sounds

"Something that we advocate at Volition is peer review," says Gross. "We involve each other while we are designing sounds, before they are done. Showing your work when you're halfway through it is something that audio people can find challenging or frustrating, but this is a way that we can gradually talk about the sounds before we actually implement them in the game.

"So by the time they go in we've already had gone over them two or three times. By creating an environment where it is safe to share your sounds while they're in progress really helped us nail it before implementation because we knew there wasn't a lot of time to iterate."

8. Mount a PR Campaign

"Audio is one of the areas with the biggest disc footprint, and there are a lot of people vying for resources -- whether that's the CPU, RAM or disc footprint and rightly so it does become a bit of PR campaign to get those resources," says EA's MacPherson.

"It's important to evangelize upwards the importance of audio, because it's not as tangible a discipline as graphics or gameplay. With graphics you can pause a picture, and anybody can look and see if something's wrong immediately, but it's not the same for sound. Unless you point something out specifically, people maybe think it's because the graphics or gameplay is better. They only really notice audio when it's not good."

To help win support, FIFA's audio team uses AV comparisons where they show footage from the game with poor or limited audio and then explain or show how giving more resources to audio could improve the experience.

FIFA 12

9. Defy Logic

"In games people often go for the more logic-based approach, where if an object is in this place then it should make this sound. It's like a machine: you put sounds on objects and then they just mix themselves," says Playdead's Andersen.

"I am much more into a subjective mix. I mix it so that you always hear what you are approaching, and as soon as the objects are no longer important to the player, I get rid of them. I found it important to have the boy in Limbo at the center of sound perspective at all times, even if he moves away from the center of the screen. I think it makes perfect sense, because the player takes on the role of the boy in Limbo, so the sound follows the boy, not the environment."

10. Get Included and be Inclusive

Audio teams need to get involved earlier in the development process, says Volition's Gross. "There's a perception that because a lot of the audio work comes at the end that we don't need to be involved until the end," he says. "But by being involved from the very beginning, we can expose hidden work in other people's plans and sometimes change these plans."

It's not just about audio muscling in; it's also about audio opening up. "People can be a little intimidated talking to audio people because they don't know the language that we use, but they don't need to," says Gross. "We need to stop thinking of ourselves as separate and get involved in the planning. We need to talk to people, invite them into our offices, and just get this rapport going. A lot of it is on us in audio to go out and insert ourselves. We need to say to people that we are part of the team, and we're going to make your stuff sound amazing."