Dungeon Keeper utilises SoundFont technology to produce atmospheric sound effects. Bundled with the game are three .sbk files (sbk standing for SoundFont Bank): bullfrog.sbk, atmos1.sbk, and atmos2.sbk, each containing dungeon-themes wave files. These are used as instruments for music.dat (which is actually a MIDI file and has nothing to do with the game's soundtrack, which is in Red Book format (played from the CD)). If the game detects a Sound Blaster AWE32 or AWE64, one of the SoundFont banks is loaded at random and the MIDI tune plays, and the player is greeted by drops, screams, and other dungeon-themed sounds upon starting a game. It is for this reason that 'Creative AWE32 or AWE64' is the only MIDI option available in the DOS version.
It is also possible to have the game play one's own sound effects. This is accomplished by manually loading a SoundFont Bank and running the game with the -usersfont parameter. In late 1997, Creative Labs had several sample Dungeon Keeper SoundFont Banks available for download, which can still be downloaded thanks to the Wayback Machine. This is a little-known and forgotten-about customisation aspect of the game.
Unfortunately, this entire feature (both parts) works only on the Sound Blaster AWE32 and AWE64. Not even later Sound Blaster cards (Live!, Audigy, X-Fi, etc.) that also support SoundFont technology give you atmospheric sounds in Dungeon Keeper.
Dungeon Keeper seems to be one of the more notable (if not, the most notable) game to utilise SoundFont technology in the late 1990s, as Creative advertised the game's SoundFont support on their website and had some pages detailing the feature.
Starting with version 0.4.6.1896, Dungeon Keeper FX Unofficial recreates this functionality by having the wave files play from sound.dat, without requiring an AWE32/64 card (because no modern system supports them, and those cards haven't been supported for donkey's years). Because they're no longer played as MIDI, when they play is much more random (also, all three sound sets have been merged into one, so you'll always get the all of the sounds). Starting with KeeperFX Unofficial 0.4.7.1973, custom sound support is reintroduced, in the form of a setting in KeeperFX.cfg that specifies which sounds to play. It is possible to add sounds to sound.dat and set them as the sounds to play.
A late 1995 trailer features sounds from bullfrog.sbk.
- ↑ Dungeon Keeper trailer, late 1995.