Module File Formats

The following formats can be edited by ModPlug Tracker:

MOD: ProTracker / NoiseTracker Music Module

The MOD format is the most widely supported music module file format. If you heard about "Only Amiga makes it possible", you probably know the story of MOD music. Anyway, this is probably the oldest music module file format, and has a lot of limitations: you may be able to edit some features in ModPlug Tracker, but you'll lose some information after saving the song to disk. Here is the limitation of the MOD format: I personnally don't recommend using MOD files. If you're familiar with MOD effect syntax, you should edit XM modules, which have pretty much the same effects, and a lot more features. XM songs are also quite popular on PC.

S3M: ScreamTracker III Music Modules

ScreamTracker III is probably the first big impact in mod music on the PC platform. It has all the features of the mod format, and introduced a lot more features. It's still limited compared to XM or IT modules, especially since it lacks volume envelopes, but is still a very powerful format. One of the big advantage of S3M modules is that it's almost as popular as MOD songs, and will be played by any decent mod player. The only thing S3M songs don't allow is instruments and everything that comes with it (envelopes, note mapping), and have the same mod limitation of 64 rows per pattern. Song comments will not be saved in S3M modules, and there is a maximum of 32 channels. Besides that, it's still an excellent format, although some older players may not recognize the new S3M effects introduced by Impulse Tracker, like Tempo Slide (T0x, T1x), Channel Volume (Mxx, Nxy), Panning Slide (Pxy) and PanBrello (Yxy), and won't play S3M with more than 16 channels.

XM: FastTracker II Music Modules

XM modules are a superset of MOD modules. You can find everything you have in MODs, but there is more effects, no sample size limit (Well, ModPlug has a sample limit of 16MB/sample), support for 16-bit samples, a variable number of rows per pattern, up to 64 channels, and the introduction of a powerful new feature: the instruments. Before, instruments and samples were quite the same thing. In XM and IT modules, an instrument can have more than one sample. For each note, you can associate a different instrument, a volume/panning envelope, and a fadeout volume. The only problem with XM modules, is that samples can't be shared by different instruments. So when you associate a sample in two different instruments, ModPlug will save the sample twice, in order to preserve XM compatibility. The main advantage of XM over IT modules is that they are more supported on PC than IT modules - which not a lot of players support yet.
Note: FT2 will not load XM modules with an odd number of channels, or modules with more than 32 channels.

IT: Impulse Tracker Music Modules

Like XM modules are an extension of MOD modules, IT is a superset of S3M. Impulse Tracker Modules represent a major improvement over the other ones. If you never used instruments with FastTracker, IT songs could be considered exactly as S3M songs. However, the major improvement, besides the fact that, like FastTracker II, it doesn't have the 64-rows limits in patterns, and can have comments in the song (No need to edit sample names anymore), is the support for volume/panning/pitch envelopes and especially NNAs. The New Note Action option means that when you play a new note, the old one doesn't have to be cut abruptly, but can fade in the background, for example. If you are just starting to write your own mod music, I recommend starting with S3M modules (Or IT modules with no instruments), and then get yourself used to the volume envelopes and NNA effects.