Music disk

Module files (MOD music, tracker music) are a family of music file formats originating from the MOD file format on Amiga systems used in the late 1980s. Those who produce these files (using the software called music trackers) and listen to them, form the worldwide MOD scene, a part of the demoscene subculture. Module files are often chiptunes.

The mass interchange of "MOD music" or "tracker music" (music stored in module files created with trackers) evolved from early FIDO networks. Many websites host large numbers of these files, the most comprehensive of them being the Mod Archive.

Nowadays most module files, including ones in zipped form, are supported by most popular media players such as Winamp, VLC, Foobar2000, Amarok, Exaile and many others (mainly due to inclusion of common playback libraries such as libmodplug for gstreamer).

Module files store several "patterns" or "pages" of music data in a form similar to that of a spreadsheet. These patterns contain note numbers, instrument numbers, and controller messages. The number of notes that can be played simultaneously depends on how many "tracks" there are per pattern. They also contain digitally recorded samples as well as coding for sequencing the samples in playback. The programs that are used to create these files provide composers with the means to control and manipulate sound samples in almost limitless ways to produce music.

A disadvantage of module files is that there is no real standard specification in how the modules should be played back properly, which may result in modules sounding slightly different in different players. This is mostly due to effects that can be applied to the samples in the module file and how the authors of different players choose to implement them.

Each module file format builds on concepts introduced in its predecessors.

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Wikipedia