 Version 2 of the format (ADX2) uses the HCA and HCA-MX extension, which are usually bundled into a container file with the extensions ACB and AWB.The AWB extension is not to be confused with the Audio format with the same extension and mostly contains the binary data for the HCA files.ADX is a compressed audio format but unlike MP3 and similar formats, it doesn't apply a psychoacoustic model to the sound to reduce its complexity.