Before starting this tutorial, I assume you have knowledge of how to go into RCM, get into hbmenu, and use layeredfs. I will not be covering or helping with these as this is a tutorial, not an FAQ.

Requirements
-Windows PC
-Switch ()
-a brain
-layeredfs already setup
-title id of your game
-about 15 minutes
-the song you want
-audacity
-StreamTool

Step 1:
Download StreamTool https://github.com/slashiee/StreamTool

Step 2:
Run setup.bat

Step 3:
once its done, it should open a page in your browser to the ffmpeg site, follow what it says in the cmd window. (download ffmpeg and drag into the folder)

Step 4:
Get your song in mp3, other formats are ok, but I use mp3 personally.

Step 5:
Open that song in Audacity

Step 5.5:
(Optional) Amplify or De-Amplify the song, it might be too loud for the game, or for a game like splatoon 2 it might be drowned out by the sound effects.

Step 6:
Export the audio (and choose this setting)

Step 7:
Go to the folder where you put StreamTool, and drag that audio you exported as wav onto

Step 8:
Wait for the conversion to finish, then you will find the bfstm with the same name of that song.

Step 9:
You are finished, rename the the bfstm to its respective name.

Step 10:
Place it in its respective place (atmosphere/titles/<titleid>/

Step 11
Test it in-game, it should work.

Step 12:
???

Step 13:
Profit.


I hope my tutorial worked for you! I recommend bookmarking this if you forget, or as a cheat sheet if you are stuck.
~End of tutorial~

EDIT:
Oh I forgot, sometimes people convert popular music to bfstm already on http://www.smashcustommusic.com so I would look there first if it's a song from a game.
If you decide to download from here, click this.

If you download the correct BFSTM it should work, and they are looped on this site, unless it says it isn't.
If you download the incorrect BFSTM, it won't work, and may crash or it will be silent.

EDIT: 2
If you want your music to loop in-game, trim it to make it loop from beginning to end. (or what ever you decide to do, I'm not skilled at loops.)

 

[Mat37]

I don't know if you still use it or not, but I just want to let you know that I updated it a few days ago as it had a very serious bug when switching the endianness.

I'll try it out when i'll need it

 

[Jtendo]

will this work for super smash Bros Ulitamte

 

[Deleted User]

will this work for super smash Bros Ulitamte

no as smash ultimate uses .lopus which is a renamed .opus file

 

[Deleted member 340473]

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[eliboa]

Super dumb question but when I read (10) I realize, atmosphere "replaces" files in memory / creates a virtual FS where your files in atmosphere/title/XXX overwrite the OG ones? Sort of like when you load custom HD textures on emulators and the emulator just replaces the original file with the one you put in a directory, or Skyrim mods on PC and virtual filesystem from the mod manager, this is the same concept then?

Reason I ask is because for some games people wonder "if it will be possible to mod" to which the answer would be always "yes!" as you can extract the NCAs, then assets then just put whatever you want as replacement, no?

Yes, this is the purpose of fs_mitm module in Stratosphère. It creates a virtual FS (Layered FS) by merging files from SD ( in atmosphere/title/XXX) with rom storage. Files from SD are prefered when merging. So yes, LayeredFS lets you mod any game or title by replacing loose files (such as BFSTM files) or exeFS files.

 

[Deleted member 340473]

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