Panning was very important in respect to consistency, and something we have seen many AAA titles treat irreverently (although probably not deliberately). Dialogue is consistently center only, with the exception of positional pedestrian or soldier dialogue. Music remains Left/Right only, ambience quad, and hud is center. No matter what presentation device is used, the same panning map is applied.
This is also reflected in the way we approached audio compression, ensuring that the overall fidelity of the audio in cutscenes matched that of the in-game dialogue, etc. as closely as we could achieve. Our goal of consistency also carried across between the two major platforms. The Xbox 360 and PlayStation 3 mixes, when run side by side, are identical, and even though the PS3 sounds is a little different because of our use of mp3 compression over XMA, mix levels and panning are absolutely consistent across the two platforms. This was a major achievement in terms of meeting our primary goal.
Following recommended loudness guidelines, and measuring via the NuGen VIS-LM Meter, we initially aimed for -23 ITU for all areas of game play, however soon discovered that, while it made sense for cut scenes and some quiet missions, this felt too quiet and inhibiting for our title overall, particularly for intense action section of the game.
The long term metering expressed in the ITU spec was developed for broadcast program content, and suits 'predictable' program content usually around one hour or half an hour in duration, and in this respect a single long-term number can't be applied as easily to video games that have indeterminate lengths and unpredictable content.
The strategy we adopted wasn't a conscious one, but more an observation based on what sounded good. We noticed different sections of the game naturally pooling into different loudness ranges by simply mixing to what sounded right. We noted a 'range' of long term loudness measurements which can be anywhere between -13 and -23 LU, based on the nature of the action.
These numbers are what we are calling, for now, our "Long Term Dynamic-Range", a grouping of loudness measurements that apply to certain types of game play or presentation elements, in our case -13 to -23. In essence I think what is required here is a method of measuring all these different aspects of the game within a short time window, around 30 mins to make a single overall loudness measurement useful. This is not always an easy approach when the game isn't structured in that way.
Even when a game is perfectly balanced, it can be ruined when the player has a poor audio setup. There isn't much we can do as content creators to accommodate every different home audio system, other than turn up at their homes and offer to calibrate it for them, but we can offer a couple of listener modes that address the common problems associated with the differences between "high end" home-theater playback systems and more humble speaker systems.
This problem is apparent here at work too, as many of our meeting spaces and offices display wildly varying degrees of speaker abuse (comparing speakers to scolded children, stuffed in the corner facing the wall or behind a monitor, would not be too far an analogy to describe the way these objects are treated). So, this is the first time we have introduced a setting in the sound options that caters for either the home theater setup or the TV speakers.
These are essentially two different mixes of the game, the home theater version being the one with the most dynamic range and the listening levels in the ranges described above, while the TV speaker setting adds some subtle compression to the overall output, allowing players to hear quieter sounds in a more noisy home environment, and also pushes up some of the overall levels of dialogue.
In the past we have attempted to do both with one single mix setting, by mixing in our high end mix theater, and then by "tweaking" that same mix while listening through TV speakers; however, this compromised the home theater mix we had spent so much time on.
By allowing two completely different mixes to co-exist and be chosen by the user, we seem to have got around the issue of supporting the two most common listening environments available among our audience. In retrospect I also feel we could have labelled the "home theater" mix as the one to use for "headphone users", as that would be the obvious choice, but being the default setting it should be reasonable to expect most headphone players will end up hearing the higher fidelity version.
Activision's internal AV lab, headed up by Victor Durling, was critical as our "third ear" in helping us to contextualize our game's levels in the wider commercial landscape. Their dedicated audio test lab utilizes Dolby metering via the LM100 and consists of two custom-built surround rooms. We were aiming for levels around that of Rockstar's Red Dead Redemption or GTA IV, however, for an action, horror title our game felt like it needed to be pushed a little louder to match competitive games in our genre.
Hence we eventually landed somewhere in the region of -19, but as mentioned before, this single number for long-term measurement made little sense to the actual practical mixing of the game from section to section. I strongly believe it is critical to have a third-party listen to the mix, and even though the communication between us and the AV lab was only via email, we got a pretty good picture of what they were hearing and could adjust accordingly.
By following a goal of consistency throughout the project on several major asset threads such as music and voice, we were able to have a great deal of control over how these sounded throughout the game, no matter what the context or the technical delivery method. This was accomplished by thinking about the mix horizontally and vertically from early production.
I think this approach throughout production came about by being conscious from the beginning of the project that we were going to be spending time on a final mix, and we knew we'd be under pressure in those final few weeks, so didn't want to have to address too much of the horizontal minutiae that belonged to pre-mixing in those valuable final days on the project. Scheduling and planning always begins from a potential ship date, and from there we work backwards through our final mix dates, through to our sound alpha dates, and then backwards further to the booking of production resources like voice-over studios.
I believe consistency is an overall approach that can be brought to any mix project, no matter what the genre or the playback context. However figuring out the best approach is often a complex cultural and contextual negotiation in and of itself.
Given all of our metering and various loudness level numbers, one may think the mix is a dry, cold, technical exercise, however the question we asked ourselves every day on the mix stage was simply, "Does it sound good?" and by using a combination of common sense and metering, made any necessary adjustments. One of the defining measurements of success, in the end, became that if you closed your eyes, you would find it difficult to discern if you were hearing a pre-rendered cutscene, a game engine cutscene, or in-game moment. Listening back post-release, after having finished work on the game, I believe we achieved this goal exceptionally well with a very small audio team.
Rob Bridgett: Audio Director / Mixer / Cutscene Sound Design
Scott Morgan: Audio Director / Composer / Sound Design
Peter Mielcarski: Audio Programmer
Roman Tomazin: Technical Sound Designer
Rob King: Voice Director