Editing Music

There are 4 types of files you mostly need to concern yourself with in music modding:

• BFSTM (.bfstm) “Binary Cafe Stream” files
• BFSTP (.bfstp) “Binary Cafe Stream Prefetch” files
• BFWAV (.bfwav) “Binary Cafe Wave” files
• Bars (.bars) files

Splatoon 2 saves its music as streamed BFSTM files, located in Sounds/Resource/Stream and usually named STRM_[CONTEXT][INTERNAL TRACK NAME](_Minigame), with the variants used in Squid Beatz using the Minigame extension. You can also find Ambience tracks here.

In Sounds/Resource there are files named Bgm[CONTEXT].bars, and these files contain BFSTP files that share there names with corresponding BFSTM files. These files are needed to preload the audio that is loaded in the given context, to save the game the resources that would be needed by having every track available at once (Squid Beatz can afford to load 94 audio files at once because it takes place in a black void). Each BFSTP contains compressed data of their respective file and only play for 1 second before switching over to the BFSTM to play the rest.

Bars files also contain BFWAV files, used for shorter audio clips, but primarily for sound effects. To learn more about how to edit sound effects, check out the main page on the topic.

The specific music track that players for a given Map can be found in Mush/MapInfo.release.byml, where the BgmType parameter selects a track from the loadlist. The name used matches the internal name, but it is currently unknown how the STRM_[CONTEXT] part of the file's name is handled.

First of all, find the Bars file that is used to load the track, and check the frequency (typically 48000Hz, but you should always check). Using LoopingAudioConverter, convert the original into a more typical file format. Compare the original file with the one you want to use as a replacement to make sure they are of the same volume. Use LoopingAudioConverter to convert the replacement to BFSTM, making sure to set it to the correct frequency. Change the name to that of the file you are replacing, place it in your SD card at [GAME ID]/Sounds/Resource/Stream, then go and test.

By default when a track ends it will start from the 00:00 mark. You can set custom loop information by selecting “Ask for all files” under “For files with no loop information” when converting with LoopingAudioConverter. For each file, you can now set start and end times for the loop, and listen to see whether it sounds right.

If you're still hearing the original game's audio for a split second, it means you need to edit the Bars file and change the BFSTP files.