Joystiq has published a very cool interview with Kristofor Mellroth, Audio Director of Crackdown 2.
In the first game, I actually did all of the explosions, weapons, and then my teams here did all the physics stuff. And one thing that I knew I wanted to improve on this one was the fidelity and the punch. We had a very specific sound last time, and the way you would normally design weapons and explosions, we had a real-time reflection system, so it would cast rays out onto surfaces and then filter them off of those surfaces, and they gave it a real authentic, on the street sound, but it also made it so that you had to design your sound types in a very specific way. So one of the things we did this time is we switched to an all-new audio engine. Ripped everything out, and I wanted higher fidelity guns, and I wanted more punch out of everything. I’m a huge online gamer, I play a lot of Call of Duty, I play a lot of Battlefield: Bad Company 2 — those were the games that I set my sights on as far as what I wanted to compete with. So we did a gun shoot, every weapon that you hear in the game is an original recording, all new, only for us. That’s how you get your gun sound is you go to a location. We went to a couple of places — we went to the desert once and got blown out by the wind, and then I had the guys that we were working with on that session go to a specific canyon and they recorded an arsenal, everything from belt-fed machine guns to 8 gauge sawed-off shotguns. And when we worked on the sound design for the weapons, I used almost the exact same design that I did last time, as far as structure.
We do some subtle things over time, so as you level up your weapon skill, the sound design changes. I don’t know if you noticed that on the first one — it stretches out over such a long time. But if you play a level 1 agent’s firearms versus a level 5 agent’s firearms, they sound very different. On this one, we did a few subtle tweaks to that, we added another layer of weapon, we were able to refine it a lot more.
Our distant gun sounds last time worked out really well — it’s all simulated, we don’t fake any of our battle ambiences, so that’s all generated by the game.