[In a fascinating, in-depth audio article, Radical's Morgan explains the detail that went into creating the complex ambient sound for the troubled cityscape in action game Prototype.]

Prototype is a third-person, original property developed by Radical Entertainment and published by Activision Blizzard. It is an intense, open-world, free-roaming, action adventure game set in a version of New York City that gradually descends into a virtual hell by way of an outbreak of a deadly viral infection.

The game features action driven by a three-way war among the main player character, Alex Mercer; the military, trying to squash the outbreak; and a growing force of infected people and creatures.

Goals for the Ambience

The direction for ambience in Prototype was to create a living, breathing New York City; a city that felt believable and alive, adaptive and dynamic. Instead of aiming to break down the city by zones alone, the desire was to base the ambience on the objects within the game world and their relative densities, populations and emotional states.

Based on the overall design of the game design, our intention with the ambient audio was not to create a block-by-block recreation of the city, nor was it to represent any specific neighborhood or region with detailed, accurate sound.

Instead, we were after an overall feel of New York and the basic sensation that the city was itself a character that was alive and dynamic, transforming with the player's movements throughout the environment and the progression of the story.

The Manhattan (Recording) Project

Early in pre-production we made the decision to travel to New York City to document ambient sound. Our Sound Designer Cory Hawthorne and myself, equipped with M-Audio MicroTrack 24/96 recorders and custom built headset mics/preamps from Sonic Studios, combed the streets, shorelines and parks of Manhattan recording as much audio as we could over the course of a week and a half.

Our aim was twofold: to document New York audio for reference and to collect useful, high quality audio which we could then use to build our game's ambiences from the ground up. We returned from New York with about 20 hours of raw recordings.

We recorded everything from "quiet" courtyards to the noisy center of Times Square. We recorded from 40 storeys up on a rooftop and underground in the subways.

We recorded Central and Battery Parks as well as the bustling financial district and hectic Canal Street shopping district. We recorded in the rain, during the day and the night.

Although much of this audio did make it into the game, the game's ambiences are complete reconstructions and often include multiple layers of our original recordings with extra sounds added from our libraries.

Surprisingly, some of the most useful recordings from New York were those recorded at the greatest distance from individual people and cars. Rooftops, back allies, parks, and more all proved as useful as the busy street corners and pedestrian-heavy centers, mostly due to the method of implementation -- which I'll describe later.

Although our recording set-ups were stereo, some of the ambiences in the game are actually quadraphonic. We decided that light-weight, low-profile stereo equipment was actually more desirable than any kind of elaborate four-channel mic/recorder setup.

The quad ambiences in the game ended up being amalgamations of two or more separate sets of stereo recordings from the same environments. Although you lose any realistic positioning with this style of recording/playback, it has the advantage of sounding denser, which was often desirable for our game.

Although many of Manhattan's neighborhoods and boroughs have distinct and unique ambiences, what we discovered after several days of recording is Manhattan has a constant drone that underscores everything in the city. You can hear it in the parks, the subways and the busy streets -- it is like a resonant note that plays continuously in the background, 24/7.

Some of our quieter recordings reveal this keynote drone so we primarily used those recordings to form the basic, four-channel building block of Prototype's New York City ambience.