Adding custom music

PWADs can include music lumps for custom music when played. Originally, these lumps were encoded in the MUS format. WAD editors need to convert between that and a format used by music authoring tools, such as MIDI.

Many modern ports will accept MIDI lumps.

Ingredients
To add music to a wad you will need:


 * a midi file that you want in your level
 * WAD resource editor such as XWE

Name your MIDI file
If your map occupies the MAP01 slot, you will have to rename the midi file to D_RUNNIN for it to work properly.

See music for a list of names used on other map slots.

Import the MIDI
Open your map in XWE. At the bottom of the screen you will see a tab that says music. Double click on that and open the MIDI file that you renamed in the previous step.

Creating MIDI files
There are several sequencers that can create MIDI files. Just search for MIDI sequencer and you'll most likely find one that suites your needs.

Seamless looping
When creting a MIDI file make sure that no notes stretch out beyond the end of the MIDI file, or else your song will end with a silent bar of music.

MUS format

 * Doom MUS format uses 9 channels apart from MIDI's 16 channels using channel 1-8 for sounds and channel 9 for drums.
 * Each channel can only play 1 note at the time, so if you want to add a chord then you have to set 3 channels to the same patch and split the notes up that way.
 * MUS format uses the same MIDI patch layout as in General MIDI.