GDM

The GDM (General DigiMusic) format is a sample-based music format similar to MOD, and is unique to the BWSB sound library. GDM is well known among MZXers due to the high number of songs converted to this format for use in MZX games.

The DOS versions of MegaZeux included a program called 2GDM, which converted several module formats (most notably S3M) into the GDM format. As MegaZeux didn't natively support S3M music at the time, 2GDM was often the only way to allow an S3M song to be used within MegaZeux.

Since version 2.80, MegaZeux is capable of converting GDM music back into S3M at load-time, so that this music can be played back using the ModPlug library used in the ports. (The alternate MZX module library MikMod, on the other hand, can play them natively.)