- Not to be confused with the Sirius XM satellite radio service, with which it has nothing to do.
XM (extended module) is an audio format introduced by (and primarily produced by) FastTracker 2, a now defunct tracker for MS-DOS. The format is also used by other trackers, such as DigiTracker and MilkyTracker.
The tracker which produced the file can be identified by means of the string at offset 38:
|FastTracker 2||"FastTracker II"|
|OpenMPT||"OpenMPT " and then the version number|
|AmigaMML||By default, "AmigaMML " and the version number; can be changed|
- The XM module format description for XM files version $0104
- The above, with a number of corrections and additions
- Errors in the XM format documentation
- Another corrected document of XM file format