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Webbased old-school Amiga music tracker in plain old javascript - Plays and edits Amiga Mod files and FastTracker XM files


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Browser-based old-school Amiga Music Tracker in plain old JavaScript.


Plays and edits Amiga Module files and FastTracker 2 XM files.
Live demo at

If you have ever heard of Protracker or Fasttracker, then you know the drill,
if not, then you are probably too young :-)


  • This tracker requires a modern browser that supports WebAudio. It's tested to work on Chrome, Firefox, Safari, Edge, Chrome on Android, mobile Safari and the Samsung Android Browser. It works best in Chrome.
  • Midi support is not available in Firefox or Safari.
  • Minimum requirements for mobile devices: IOS9 or Android 6



  • Load, play, edit and save Protracker and FastTracker 2 compatible module files
  • All Protracker audio effects are supported (99% accurate, in case of historical differences in playback engines, I tend to follow the Protracker 2.X one)
    • Portamento / Frequency slides (Effect 1, 2, 3, 5, E1 and E2)
    • Vibrato (effect 4, 6, and E4)
    • Tremolo (effect 7 and E7)
    • Arpeggio (effect 0)
    • Glissando (effect E3)
    • Sample offsets (effect 9)
    • Volume slides and settings (effect A, C, E10, and E11)
    • Position jumps (effect B)
    • Pattern breaks, loops and delays (effect D, E6, and E14)
    • Speed settings (effect F)
    • Sample Delay, Cut, Retrigger and Finetune (effect E13, E12, E9, and E5)
    • Lowpass/LED filter (effect E0)
  • Almost all FastTracker audio effects are supported (97% accurate)
    • Volume and Panning Envelopes
    • Auto Vibrato
    • Multiple samples per instrument
    • Extended volume commands
  • Next to the tracker effects, there are per-channel effects for low, mid, high frequency, panning and reverb control
  • Mute/solo tracks
  • Edit pattern data and sample properties, use ranges and cut/copy/paste for quick editing
  • Midi support (only Midi-in currently)
  • Up to 32 channels
  • Import 8bit WAV, 8SVX and RAW samples (as well as any other format AudioContext can read, like .mp3 and .ogg)
  • Integrated sample editor: Edit and slice your samples right inside BassoonTracker
  • Full Undo/Redo in pattern editor and sample editor
  • Includes the historic ST-01 and ST-02 sample disks, released in 1987 (as well as a bunch of others)
  • The modarchive API is integrated to access several thousands of music files
  • The API is integrated to access even more music files
  • Export to .mod, .xm, .wav, and .mp3
  • Connect your Dropbox account to directly read and write your own files
  • Read more in The Docs

The playback engine has gone through extensive compatibility testing, but as the Protracker code itself is somewhat messy and muddy throughout different versions, there's always room for improvement. If you find a module that doesn't sound the way it should, let me know! There are still some very specific Protracker 1 and 2 playback quirks that are not implemented (and probably never will as they are too bat-shit-crazy)

Missing features and bugs:

  • The following FastTracker features are not fully supported yet:
    • Tremor
    • "Set envelope position" command
    • PingPong Loops are unrolled to normal loops (There's no difference in sound but if you save your XM file, your samples will have changed.)
    • When writing XM files, patterns are not packed so the resulting files will probably be a little bigger than when saved with the real FastTracker 2.
  • Safari doesn't support WebAudio StereoPanners so songs will be played in mono on Safari.
  • Safari and Firefox don't support the Web Midi Api so no midi on those browsers.

Note: if you use an AZERTY, QWERTZ or DVORAK keyboard, you can set that option in the settings to have the correct layout when playing notes on your computer keyboard.

How to Build

  • The build step is optional, there are no runtime dependencies (bliss!)
  • Just open dev.html in a browser to load the plain uncompressed scripts
  • To build the packaged version:
    • If you don't have grunt installed - install it with "npm install -g grunt-cli"
    • Run "npm i" to install the Grunt build tools.
    • Use "grunt" to build the compressed files -> index.html will be created.
    • Use "grunt sprites" to build the spritesheet. This will compact all files in the "skin/src" to a single .png file and will create a spritemap.
    • Use "grunt player" to build the player-only version (you can find it the "player" directory).
    • Use "grunt friend" to build the version for Friend OS (you can find it the "hosts/FriendOs/build" directory)

Future plans

  • MIDI support -> Done!
  • Undo/redo on pattern edits and sample edits -> Done!
  • Implement local file system access
  • Export and import of .xi instruments.
  • 3SM/Screamtracker file support, maybe OctaMED too.
  • Allow synth/FM instruments next to sample instruments.
  • Although the tracker concept is awesome - it also would be nice to integrate it in a more modern "horizontal block compose" style interface where you can re-use and combine tracks/patterns in a composition instead of endlessly copying tracks.
  • Allow multiple notes per track (or at least give the option to let them play when a new note is triggered).
  • More effects (echo, reverb, flange, etc.) should probably be implemented with graphical track-envelopes instead of instrument envelopes or more numerical effect parameters. All this would require (yet another) new file format, but that seems inevitable.
  • Simpler HTML/CSS-based layout - maybe the canvas approach is too heavy for really large screens? (Done, but not maintained)
  • Plugins:
    • Jukebox plugins, filter on genre/rating/etc.: hit play and let it perform.
    • More expanded sample editor with audio processing features - probably as an external plugin.
    • Nibbles... we definitely need Nibbles. -> We do!

Player If you want to integrate the BassoonTracker playback routines in your own website, check out the "Standalone Player" examples in the "player" directory or visit the live Player demo.


Webbased old-school Amiga music tracker in plain old javascript - Plays and edits Amiga Mod files and FastTracker XM files