Soul Calibur is a fighter that dwells not only on the action, but the story as well and to accentuate all the different scenes, the romantic, exciting and eerie moods, the producers make use of the OST.
Since the game is ultimately a game about three holy swords against the evil weapon, expect a lot of grandly orchestrated pieces that dwells on the heroic atmosphere.
The wielders of the Soul Caliburs are from different countries, e.g. Europe, Korean, China etc, to go with the image of these countries, there would be music of various styles in the double disc OST.