Module file

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 trackers) and listen to them, form the worldwide MOD scene, a part of the demoscene subculture.

The mass interchange of "MOD music" or "tracker music" (music stored in module files created with trackers) evolves 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).

§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. 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.

Module files are also referred to as "tracker modules", and the process of composing modules is known as tracking. 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.

§History

The worldwide MOD scene, closely related to the Demoscene, started on the Commodore 64 with SID music used on video game cracks. It spread to the Amiga and eventually to the PC. Soon after Amiga computers with the Paula sound chip were introduced, Karsten Obarski wrote the sequencer software Ultimate Soundtracker in 1987 which was based on the tracker concept invented by Chris Hülsbeck. Ultimate Soundtracker was a commercial product, but soon shareware clones such as NoiseTracker and ProTracker, being direct descendants from the original Soundtracker code, appeared as well. Protracker ran on newer versions of AmigaOS and was very stable to boot. Some trackers such as OctaMED took advantage of tricks like software mixing to give the artist more flexibility in song writing. Modules were originally intended to be used in video games, but the demoscene and musicians started composing them for demos. Coincidentally the demoscene, being full of talented programmers and musicians, pushed trackers, and the MOD format quickly became one of the most popular music formats across the home computer platforms. Among the reasons for the format's success was its comparably low CPU overhead (on the Amiga it was possible to process all the music in the video memory, skipping the CPU altogether), small file sizes and relatively good sound quality, which mostly depended on the amount of storage that could be used for the music, rather than the capabilities of the format itself.

Many demosceners wrote their own trackers with features not present in Ultimate Soundtracker, and musicians took full advantage of these features, creating music as efficient as the code in demos. As technology advanced, computer audio matured and with MS-DOS, PCs had even more capability. Many PCs used Sound Blaster cards which allowed for many audio channels. As the demoscene moved onto these new computers, they would write new trackers for them. FastTracker 2 was one such program. Written by two members of the demogroup Triton, it introduced a new format called XM or extended module. FT2 was able to use 32 channels at once and added many useful commands and other features. It was not alone however, Scream Tracker had a different layout that some preferred and had support for FM synthesis on cards that included an OPL 2/3/4 chip. Impulse Tracker, which based its interface off of Scream Tracker's, further advanced module composing adding filters and 64 channels of audio.

Sound quality would also be very consistent on all sound cards with the ability to play digitized sounds, partly solving the issue with several competing (and widely different) sound card standards on the PC in the early 90's, where a MIDI song written for the Roland MT-32 would sound entirely different on the Adlib or one of the many competing cards at the time. The music could also be easily programmed to have multiple self-contained loops, which then could be triggered by the game as needed, creating dynamic soundtracks.

§Scene

Tracker music is characteristic in that it is made by hand, distributed as open source, and executed in real-time. It has seen tens of thousands of members come and go and has developed several styles of music unique to the genre. Composers adapt to the technical limitations as well as the cultural conditions, where resources were often reserved for the visual content. The process of composing module files, known as tracking, is a highly creative and skillful activity that involves a much closer contact with musical sound than conventional composition, because every aspect of each sonic event is coded, from pitch and duration to exact volume, panning, and laying in numerous effects such as echo, tremolo and fades. Once the module file is finished, it is released to the tracker community. The composer uploads the newly composition to one or more of several sites where module files are archieved, making it available to his or her audience, who will download the file on their own computers. By encoding textual information within each module file, composers maintain contact with their audiences and with one another by including their email addresses, greetings to fans and other composers, and virtual signatures. Although trackers can be considered to have some technical limitations, it does not prevent a creative individual from producing music that is indiscernible from professionally created music. Many tracker musicians gained international prominence within MOD software users and some of them went on to work for high-profile video game studios, or started their own. Notable artists include Andrew Sega, Jeroen Tel, Bjørn Lynne, Alexander Brandon, Skaven, Purple Motion, KFMF, 4mat, Jesper Kyd, Markus Kaarlonen, Michiel van den Bos, Dan Gardopée and Elwood. Deadmau5 and Erez Eisen of Infected Mushroom have both used Impulse Tracker in their early career.

Tracker music has been featured in numerous computer games, as well as in electronic dance music productions. A well-known example of a game featuring tracker music is the science fiction shooter Unreal, developed by Epic Games. The music team composition constructed the entire's game soundtrack using module files, which allowed both a relatively high sound quality and a good assortment of interactive possibilities. Unreal Tournament, Deus Ex and Hitman: Codename 47 also featured tracker music.

§Popular formats

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

Sound/Pro/Noisetracker module (file extension .mod, or mod. prefix on Amiga systems)

This is the original module format. Uses inverse-frequency note numbers. 4 voices, with up to 32 in later variations of the format. Pattern data is not packed. Instruments are simple volume levels; samples and instruments correspond one-to-one. 15 instruments in the original Soundtracker, 31 in later trackers. This format was originally created to be easily playable with the Amiga hardware, since it was equipped with a four-channel DAC. The CPU has to do very little work to play these modules on an Amiga. Many games utilize this format - often with small player programs included. In the early 1990s, usage of this format with games was widespread across platforms, with games on PC and Nintendo systems utilizing it, as well.

The original .mod extension is actually not a suffix on the Amiga, but a prefix; mod.* is the standard naming convention on the Amiga, and same prefix standard is used in basically all the other various sample/synth-trackers ever made for the Amiga - Art of Noise, AHX/THX, Musicline, Startrekker, FutureComposer, SidMon, Brian Postma's SoundMon etc. The majority of the "oldschool format"-players for Windows, Linux, Mac OS etc. will, when trying to load an "original" mod.*-file (or ahx.*, bp.*, fc14.* and so on), simply not play it due not analysing the file to determine the type - they only check for a filename extension as a suffix. Simply renaming the file from "mod.filename" to "filename.mod" is usually a sufficient workaround.

Oktalyzer (originated on Amiga computers)

This was an early effort to bring 8 channel sound to the Amiga. Later replayers have improved on the sound quality attainable from these modules by more demanding mixing technologies.

MED/OctaMED (originated on Amiga computers)

This format is very similar to sound/pro/noisetracker, but the way the data is stored is different. MED was not a direct clone of SoundTracker, and had different features and file formats. OctaMED was an 8-channel version of MED, which eventually evolved into OctaMED Soundstudio (which offers 128-channel sound, optional synth sounds, MIDI support and lots of other high-end features).

AHX (originated on Amiga computers)

This format is a synth-tracker. There are no samples in the module file, rather descriptions of how to synthesize the required sound. This results in very small audio files (AHX modules are typically 1k-4k in size), and a very characteristic sound. AHX is designed for music with chiptune sound. The AHX tracker requires Kickstart 2.0 and 2 mb RAM memory.

.s3m (originated in ScreamTracker version 3 for PC)

Up to 16 or more voices. Samples can specify any playback frequency for middle C. Simple packing of pattern data. Introduction of several new controllers and a dedicated "volume column" in each voice to replace volume controllers. Predictable support for stereo panning and AdLib FM synthesis instruments (although the latter is rarely supported in playback software).

.xm (originated in Fast Tracker)

Introduction of instruments with volume and panning envelopes. Basic pattern compression, no sample compression. Added ping-pong loops to samples.

.it (originated in Impulse Tracker)

New Note Actions let the previous note in a track fade out on top of the next note (providing greater effective polyphony). Instruments can now share a sample. Adds some new effects such as a resonant filter. Better pattern compression. Added sample compression. Added sustain loops to samples.

.mo3

Created by Ian Luck to use MP3/Ogg compressed samples

.mtm

MultiTracker modules

.umx

Unreal/Tournament music package. This is actually a standard Unreal package file that wraps one .mod, .s3m, .it or .xm file so it can be accessed from within the game.

§Software module file players and converters

Many of the listed software use the modplug engine from the open source multimedia framework gstreamer.

§Players

• XMPlay (Windows), from Un4seen Developments, which also created the MO3 format
• OZMod (Java, cross-platform, free source code)
• Winamp (Windows)
• AIMP
• BZR Player (Windows)
• foobar2000 (Windows) (with foo_dumb plugin)
• Mod4Win (Windows), one of the first Windows Mod player
• K-Multimedia Player (Windows)
• Quintessential Player (Windows)
• Sonique (Windows)
• VLC (Linux, Mac OS X, Windows)
• Audacious (Linux)
• XMMS and XMMS2 (Linux/UNIX)
• Totem (Linux/UNIX)
• Music Player Daemon (Linux/UNIX)
• DeaDBeeF (Linux/UNIX, Android)
• MikMod (Linux/UNIX/DOS)
• Neutron Music Player (Android OS, BlackBerry 10/PlayBook)
• Modo Computer Music Player (Android OS)

§Converters and trackers

• Cog (Mac OS X)
• Amarok (Linux/UNIX)
• Audacious (Linux/UNIX)
• ModPlug Tracker (Windows)
• Unix Amiga Delitracker Emulator (Linux/UNIX)
• TiMidity (Linux/UNIX)
• OctaMED (Amiga)
• Renoise (Windows)

§See also

• Tracker
• Category:Tracker musicians
• Demoscene
• Computer music
• Video game music

§References

§Further reading

Leonard, Andrew (29 April 1999). "Mod love â€" With their ears, their computers and a little code, "mod trackers" build their own worlds of sound". Salon. Salon Media Group. 

§External links

• The Mod Archive
• Amiga Music Preservation