Ascaron Entertainment lead audio designer Lars Hammer paid a visit to the company's blog on IGN to share a few details about the 5.1 surround sound we can expect from Sacred 2: Fallen Angel.
Admittedly, 5.1 sound effects have been around for a while, and, basically, they have become a standard feature of current games. But, technically speaking, what exactly is a 5.1 effect? It is a mono sound, which is arranged in the space around the listener using a surround setup (i.e. with a minimum of four, usually six to eight speakers). A bird flying past behind the listener's back is an often used and realistic example.
And how is music played back in computer games? Usually, you put a piece of stereo music on the two front speakers (or spread the signal on all speakers - still, it's nothing but a stereo track with left and right channel information). In the 1970's several musicians and bands found out that four speakers instead of two will give you an entirely new listening experience - quadraphonic sound was born. While multi-channel music was forgotten again shortly afterwards, the success of 5.1 home theater systems lead to its eventual revival and use on audio DVD's and SACD's.
There are several ways of using the additional speakers in 5.1 mixes. From placing individual instruments between the front speakers (using the back speakers only for spatial effects, e.g. Mark Knopfler - "Sailing To Philadelphia 5.1") to choosing extreme positions for individual instruments "in" the speakers (e.g.The Eagles - "Hell Freezes Over DTS"). A very "spaced out" example is the "carousal effect", thanks to which all instruments spin around the listener symmetrically (e.g. Mike Oldfield - "Tubular Bells 2003 5.1"). The last example in particular is very exhausting to listen to and definitely unsuitable for a computer game, in which the music should add to the atmosphere.
In Sacred 2 we decided to use a blend of all approaches: on some tracks the instruments are separated clearly on different channels, on some other tracks the sound moves through space, not around the listener as on the Oldfield mix. In any case, you hear the difference at once: while the sound used to stay in the front speakers as if it were locked in there, it suddenly becomes "3D" through 5.1 and gains a depth it never had before.