X4: Foundations

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About this mod

Adds music from previous X-games and unofficial X-OSTs with a big set of custom choices and modularity. For X4 4.00 and DLCs, compatible with all but other music mods.

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Latest news
02 Apr. 2021: Legacy Music 1.20 for X4 4.00, Split Vendetta and Cradle Of Humanity has arrived at last! You don't need to have the DLCs for the mod to function but without them you won't have the music that they add so the experience will be incomplete and slightly buggy. The changes in this version aren't really big - a few tracks were reassigned between the pools and packs, most notably a bunch of tracks that were previously moved to Full pack were returned back to Basic as I slightly reconsidered my standards of "too much" percussion and speed. You can read the full 1.20 changelog here.

! Read first !

If this is your first visit ever or since previous version please carefully study packs and playlists overview and setup guide for better understanding

If you hate dark ambient 'music' that interrupts normal sector music check out my mod that fixes it: X4 No Dark Ambient

You may be interested in my other mod that prevents combat music from playing: X4 No Battle Music

Always place all X4 mods into game root folder (unless it's player logos)


I saw X Rebirth Ambient Music mod here on Nexus and decided to try it. When I looked inside of the mod files I actually changed my mind because I saw the gameripped music in awful XWMA-96 format as X Rebirth provided. Not to mention that X Rebirth OST has much more divine music that wasn't included in that mod or the game itself.

This all inspired me to make this mod with the best X-clusive selection of X-tracks for you. The X4: Foundations ambient music tracks have a very distinct style - slow, spacey and ethereal, slightly muffled and reverbing, with gentle synths and no or very mild percussion. The XR music blends good with this style unlike some of the tracks from earlier games like X3, X2 or X-Tension which are a whole other animal. Because of this stylistic variety I decided to create various music packs for differing player tastes.

Packs and playlists overview
Basic pack

Most co
rresponding to the musical style of original game, heavily leaning towards slower and quieter non-percussive ambient music:
Adds aesthetically fitting X Rebirth and missing X4 music tracks in Vorbis-356 format where possible*

Available Basic pack playlists:
1-A [Default] - one global sector music pool with random track selection
1-B [Combat Music Only] - only combat music is added if you want to play with vanilla sector music pools

Extended pack

An attempt to extend the range of music tracks in accordance with aforementioned ambient music style:
Basic plus aesthetically fitting X3, X2, X-Tension music tracks in Vorbis-356 format where possible*

Available Extended pack playlists:
3-A [Default] - one global sector music pool with random track selection
3-B [Default + XT] - one global sector music pool with random track selection; X-Tension music is added

3-C [Race Specific] - racial core sectors have unique nonoverlapping music pools with random track selection
3-D [Race Specific + XT] - racial core sectors have unique nonoverlapping music pools with random track selection; X-Tension music is added

Plus all Basic playlists included!

Full pack

This is your go-to pack if you want to have all X-games music disregarding its style and use all possible playlists:

Extended plus everything from X4, X Rebirth, X3 and X2 that was excluded from previous packs and playlists in Vorbis-356 format where possible*

Available Full pack playlists:
5-A [Default] - one global sector music pool with random track selection
5-B [Default + XT] - one global sector music pool with random track selection; X-Tension music is added

5-C [XR & X4 Only] - one global sector music pool with random track selection; only X Rebirth and X4 music is played
5-D [X3 Only] - one global sector music pool with random track selection; only X3AP and X-Tended - Terran Conflict music is played

5-E [XT & X2+ Only] - one global sector music pool with random track selection; only X-Tension, X2 and stylistically similar X3TC Daniel D. Finney music is played

Plus all Basic, Extended and X-Classic playlists included!

X-Classic pack (AKA Dinosaur edition)

For those nostalgic and conservative X-Dinosaurs out there that need nothing else:
Completely replaces all music with tracks from X-Tension and X2 in Vorbis-356 format where possible*

Available X-Classic pack playlists:
7-A [XT & X2 Only] - one global sector music pool with random track selection; only X-Tension and X2 music is played

Lite versions

For people lacking strength in areas of disk space, internet bandwidth or audiophilia:

Very special versions of Basic, Extended and Full packs with removed menu tracks and music in Vorbis-192 format where possible*

Lite versions playlists have same logic as non-lite but start with 2, 4 and 6 respectively

*Daniel D. Finney's X Rebirth OST part was provided to me in MP3-256 format.
*All X-Tension and some X2, X3 tracks were never released in OSTs and are avaliable only in gamerip quality which varies from MP3-320 to MP3-56.

Setup guide

  1. Completely delete previous version of the mod if there is such.
  2. Extract "Legacy_Music" folder from archive into [X4 root folder]\Extensions\.
  3. Extract a desired playlist file ("sound_library.xml") from "!Playlists" folder into [X4 root folder]\Extensions\Legacy_Music\libraries\. You can always replace it with any other playlist from your X4LM pack by simply overwriting the previous "sound_library.xml" in aforementioned "libraries" folder. You can also easily check what playlist you have installed previously by opening active "sound_library.xml" in any web browser.
  4. Make sure you don't use any other soundtrack mod that replaces sector, combat and menu music sound IDs in "sound_library.xml" (including any other X4LM pack) because all extensions are loaded in alphabetical order and the latter mod will override the preceding if they replace same IDs.
  5. Make sure mod is enabled in game's extensions menu (usually it is by default).
  6. Have fun, it's mandatory.
  7. ???
  8. Profffitssssssssssssss

Known issues

  • X4 1.60 update added 40 Alexei Zakharov's X Rebirth and X3 music tracks, why are their "duplicates" still bundled with the mod? All in-game legacy music tracks have long linear starting fade-in and ending fade-out mixed into them. This leaves questions as to why it was made since native X4 sector music tracks don't have such long fade curves and also since the audio engine clearly has its own working fade-in and fade-out functions. So the bundled music tracks aren't exactly duplicates but non-fading mixes from the OSTs and as quality is very important for me I've chosen to keep them as long as in-game legacy music tracks don't get proper default mixes.
  • Some mods that add new sectors don't work with X4LM playlists. All sector music pool sound IDs used in Legacy Music are strictly vanilla in terms of their names and assignment to sectors - the only thing changed is music track content in the pools themselves. Mod devs that add new sectors should simply refer those to X4 3.00 vanilla music IDs or use no refs so a sector defaults to "music_soundtrack_periphery". When they use outdated pre-3.00 IDs or custom unique IDs they unintentionally create compatibility issues for anyone who is going to use their mod.

Mod development status

  • I'm open to problem reports, suggestions and requests!
  • You can expect future mod improvements like game and addon compatibility updates, enhanced music track quality when it's possible and etc.
  • Steam workshop versions will likely be released in future.
  • Detailed tracklist article may be released in future.
  • All planned packs and playlists have been released.
  • I am researching for a way to integrate Opus codec support into X4 DLLs and FFMPEG instance. Given that Opus is currently the most efficient audio compression format its use will allow to decrease mod file sizes without quality loss. If you have experience with codec libraries and DLL recoding I can really use your help! I do however understand how difficult it can be without X4 source code so chances are it will never happen unless Egosoft does it themselves.

Credits and legal information

  • Big thanks to ziev217 for his X Rebirth Ambient Music mod that inspired me and helped to get X4LM working. I've also read his X4 music modding guide and it was helpful. Seriously, you should try it too if you're interested in making your own music mods and don't know the basics yet. No really, go and do it.
  • Enormous kudos to Thomas E. Petersen, Alexei Zakharov, Daniel D. Finney, MadMakine, Hollow Infinity, all Egosoft, publisher and Nexus mods staff that made this all possible. Well and mom and dad too.
  • I am not liable for any hardware/software damage or data loss that may or may not occur when installing or using this mod. But seriously though, don't worry, it is going to be fine.
  • All source materials for this mod were obtained and are utilized under fair use.
  • All rights belong to Egosoft and other respective owners.