The right choice of sounds used in a computer game can make a great difference in perceived overall quality of the final product. Studies have even shown that judgement of a game's visual quality depends on the quality of the sounds used alongside the on-screen graphics. For this, a group of individuals was asked to assess visual appearance of two different versions of a game which actually contained the exact same graphics, but in one case featured sophisticated audio, whereas the other version only offered bottom-of-the-line sound effects. Generally, the subjects fervently claimed that the first version had improved graphics over the latter.
Depending on the nature of the game in question, it is the task of the game sound designer to either choose appropriate natural sounds or to invent suitable artificial ones. The process requires a good deal of talent, creativity and inventiveness, in very much the same way a foley artist has to come up with ideas to simulate real-life sounds using entirely different means. Sound designer Bobby Prince offers some interesting insights into his work in his online article cited above.
A very interesting aspect of sound design is the fundamentally different approach that has to be taken in arcade and home games. Whereas the home game customer invests in a game first and then wants his money to pay off, an arcade (or coin-op) game has to grasp a potential player's attention and get him to produce a coin from his pocket to sink into the machine. Also, an arcade game has to seduce the player to spending more money on a game that typically ends after a period of 3 minutes, whereas the home gamer will be much more patient and enduring in most cases trying to get the most out of his newly purchased title even if this includes upgrading his hardware in some cases.
Another problem that cannot be understated is the disturbance that sound from an arcade machine can cause for owners of a public location (bars, cinema lounges, etc.), by playing the same teaser sequence over and over again, usually all day long. Thus, sounds for arcade games have to be designed with great care, in order to avoid sound volume being turned down by the owner of the place. A fairly successful method is to use sounds that closely resemble typical noises of the location the arcade machine is likely to be installed to. If, for instance, the game is some kind of racing simulation, it is usually wise to make it sound like TV or radio broadcast of a racing event instead of trying to reach perfection in creating to create that special 8,000-RPM engine sound. However, if the same game was to be installed in an arcade hall where it would have to compete with many other machines, it's TV-like sounds would probably not be noticed at all. In these locations, games have to create interesting and dynamic sounds to stand out from the crowd and attract attention. This conflicting situation only briefly illustrates the problems that arcade game sound designers are confronted with, for more information on the subject I recommend the excellent on-line article by Chris Granner referenced above.
Apart from in-game sounds, music plays a paramount in computer games. Unfortunately, the hard work of game composers is not often properly appreciated by game audiences. In Japan, audio CDs containing game soundtracks as well as adaptions of popular tunes featured in video games are commonplace, whereas they can hardly be found in Europe or the U.S.
Throughout the history of computer games there are a few examples where musical compositions of popular artists have been included in a game soundtrack. Some of those had been especially created for a game, while in other cases existing pieces were used. In general, game publishers were hoping to exploit the existing popularity of the featured musicians for promotion of their game title and make it more appealing to a larger audience by furnishing it with a ‘big name’. Popular examples include the famous 3D-action game QUAKE by id Software, which featured music created by Trent Reznor of THE NINE INCH NAILS or the racing game WIPEOUT XL by Psygnosis that included electronic dance music composed by various underground acts, such as FUTURE SOUND OF LONDON, who contributed a total of three tracks.
Incidentally, the exact opposite of the former situation can also be observed occasionally. For instance, the video clip of the song “Get Freaky” by MUSIC INSTRUCTOR contained sequences from the game ABE'S EXODDUS the sequel to the already popular ABE'S ODYSSEE which was due for release a few weeks after the song was first presented. It seems that both, the song as well as the game commercially profited from this strategy.
As already mentioned in the previous chapter, the creation of dynamic soundtracks is one of the most complicated ventures in computer game design. In a movie, all actions take place in a well-defined sequence, as laid down by the script. Music is most commonly added in post-production, when all film editing and cutting has already finished or is in its final stage. Therefore, a soundtrack can be developed that foreshadows particularily important events by increasing musical tension that will (hopefully) reflect back on the audience by causing a growing anticipation or even a feeling of fear. In computer games, the same process is hardly ever applicable due to their interactive nature at a given point in time, it is not known what the player will do next.
To overcome this problem, a number of concepts has been developed. One popular solution involves the use of different musical pieces for each location of the game. When the player's character enters a certain area, the music associated with this particular place is played. In a slightly more advanced version of this approach, the pieces used vary in accordance with events that might have taken place in the locations as part of story. For instance, where a joyous tune was played inside a house at the beginning of the game, a distinctly darker song would be used at a later stage in the same place after the player had discovered a mystery related to the site. In addition to game locations, music could also be linked to other characters of the game interacting with the player. Sometimes the two techniques are very effectively used in combination, with a location theme playing in the background and the character theme (which is usually much shorter) surfacing in case of a possible entry of the latter.
Another, more complex approach is to change the instrumentation of a piece of music without altering the underlying score, based on in-game events. If, for example, the player's character is confronted with some kind of danger, the orchestration of the main part could change from the soft tones of a flute to a harsh brass instrument, like a horn. This procedure can be extended to form a fully dynamic soundtrack by also changing the musical arrangement itself in real-time. This is by far the most complicated and also most debated approach, but can sometimes lead to an amazing feeling of immersion and sympathy for a character's situation. However, very much the same effect can be reached with considerably less effort through careful application of the two other methods mentioned above. In order to achieve a fully dynamic composition, a number of small patterns and motifs are created that can later be arranged into a theme. Great care has to be taken to provide for smooth transitions between the single snippets, which can be a complicated task if compositional freedom is not to be overly constrained. As mentioned, the whole approach is seriously questioned by many professional musicians and one can only guess what the ultimate outcome will be.
While the effectiveness of a good soundtrack in an adventure game is rarely disputed among gamers, the situation is entirely different for action games and simulations. In this paragraph I will present quotes from a number of interviews with game designers conducted by people from 3D SoundSurge.