Module File - Structure

Structure

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.

Module files also give a list of the order in which to play the patterns. However, the biggest advantage of MOD family over standard MIDI files is that MODs include their own audio samples and should sound exactly the same from one player to another, barring interpolation methods and any errors in players.

Module files are also referred to as tracker modules, and the process of composing modules is known as tracking, simply because the first ever module creating program was Ultimate Soundtracker, created by Karsten Obarski in 1987. Soundtracker was cloned many times, with programs such as NoiseTracker and ProTracker being direct descendants from the original Soundtracker code, and others such as MED/OctaMED and Oktalyzer being written from scratch. Such programs are called trackers in general.

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.