.XWB File Extension
What is an XWB file?
Collection of waves, or sound files, created with XACT (the Microsoft Cross-Platform Audio Creation Tool); logically grouped into a single file by an audio designer so it can be integrated into a video game.
XACT supports both in-memory banks (typically used for sound effects) and streaming wave banks (often used for background music). Audio files may be saved in .WAV, .AIFF, XMA, xWMA, and ADPCM formats.