Can also be set to a custom command (page button, foot pedal, screen gesture, hot-zone)
OpenSongApp has a built in multitrack audio player. This can be useful for rehearsing songs, where you can mute or remix the individual tracks, or play a series of backing tracks.
When loading a song and then opening the multitrack player, the app will look for a folder with the same name as the song file inside the OpenSong/Multitrack/ folder. This will be the default folder that is loaded. E.g. is your song filename is 'Love everlasting', the app will look for audio tracks in the OpenSong/Multitracks/Love everlasting/ folder. If you are using a non OpenSong formatted song (i.e. PDF or image), don't include the file extension in the folder name.
If you don't have a default multitrack folder for the song, you can stil manually select a folder containing the audio tracks once you open the player by clicking on the Multitrack folder button at the top. This can be useful if you want to keep large audio files on an external drive.
Each track will have a volume, pan, mute and solo button available. You may have to scroll left/right to see all of the available tracks. You also have a master track, which also has a boost function for quiet tracks.
You can minimise the player if you wish to continue using the app while listening (i.e. view your lyrics/chords). The player will stop whenever it is closed and your mixer settings will be saved for this song.
Stereo WAV files
Ideally headerless (i.e. PCM encoded)
16 bit
44.1kHz sample rate
All tracks must be the same duration as each other
If you try to load other file types (e.g. mp3, ogg, etc.), the app will offer you to convert them, but it will delete the original files, so make sure you keep a backup elsewhere. There is no guarantee that the conversion will be successful.
If you try to use files that do not match the specifications above, playback may fail, or will play incorrectly (i.e. at the wrong speed or with incorrect audio).
If you want to process your backing tracks on a PC, I would highly recommend Audacity. This will allow you to trim your tracks, export in the correct format and even has free OpenVino AI plugins that will try to create up to 4 tracks (Drums, Bass, Vocals and Other) from any stereo track. These can then be copied across to OpenSong/Multitrack/[SONG FILENAME].
You can also use online tools (although they may require a subscription/fee). A great one I've used is Fadr (Stems). Their basic account is free (requires an account) and you can only create the same audio stems/tracks as in the free Audacity plugin and only allows mp3 download.