Kris' Music System Format

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Kris' Music System Format
Format typeMusic
Notation typeOPL
Max channel count?
Max track count65535
Max pattern count?
Max order count?

Kris' Music System stores its music in *.kms files. Used by a number of games, the format is mostly unknown.

The format does not store any instruments, instead using four-character patch names which reference the instrument settings in a corresponding .vce file.

File format

The file begins with a header.

Data type Name Description
UINT32LE lenFile Length of the whole file, in bytes
UINT16LE unknown1 Always 0x0001 (possibly number of songs in the file?)
char[8] title Song title
UINT32LE lenTracks Length of track data, in bytes (typically number of bytes from this field until EOF, including this field). May be relevant if more than one song is in the file.
UINT16LE numTracks Number of tracks
char[4][numTracks] trackIDs List of four-character strings to identify each track, one per track, e.g. HDR1, t0s0, t1s0, t2s0, etc.
UINT32LE[numTracks] offTrack Offset of the track's first data byte, relative to the start of the track data

After this header, the tracks begin. The offTrack values are relative to this point, so one track should always have an offset of zero, which refers to the byte directly following the above header.


Each track appears to be in the following structure:

Data type Name Description
UINT32LE lenTrack Length of the track, in bytes (including this field)
BYTE[lenTrack - 4] trackData Notation data for this track

Notation data is a variable-length array of events. Each event is preceded by a delay as shown below. Events occur back to back until the end of the track.

Data type Name Description
UINT8 delay Delay
UINT8 event Event type

The data bytes following depend on certain bits in the event type.

! Finish reverse engineering this

Event byte Event Data bytes First data byte Second data byte Notes
0x00 Song data Variable - - See below
0x01..0xCF Play note 2 Unknown purpose Note duration ! In ticks? ! How to convert note numbers into pitch?
0xD9 Set tempo 2? ? ? Same as 0xDD? Except can't seem to control speed
0xDC Set instrument 1 Instrument index - Instrument #0 loads patch from instName[0]
0xDD Set tempo 1 New tempo - Tempo is in ! what? ticks per second? (lower numbers are slower.) Affects whole song, not just the current track.
0xDE Set velocity 1 New velocity - 0x00 is silent, 0x7F is full volume, high bit is ignored
0xDF Unknown 2 ? ?
0xE0 Unknown 1 ? -
0xE1 Unknown 1 ? -
0xE2 Set loop point 1 ? - Data byte is always 0xFF and occurs at start of track
0xE3 Jump to loop point 1 or 2? ? - Jumps to location where last 0xE2 event was. Always occurs at end of each track so that the song loops.
0xE4 Unknown 1 ? -
0xE5 Unknown 2 ? ?
0xE6 Transpose? 2? ? ?
0xE7 Track title Variable - - See below
0xE8 Unknown 1 ? -
0xE9 Unknown 1 ? -
0xEA..0xF0 Unknown 1 ? - Plays next few notes faster than normal then transposes the rest way down

0x00: Song data event

There will always be one track with the codename "HDR1", typically the first track in trackCodenames (but not necessarily at track offset zero) and this track has only one event, of type 0x00. This 0x00 event is in the following format.

Data type Name Description
UINT8 numInst Number of instruments
char[4][numInst] instName Instrument patch names (e.g. "DRUM" or "BASS"), not null-terminated. The instrument patch names are loaded from a corresponding voice (.vce) file, and when song event 0xDC selects an instrument, the instrument number is a zero-based index into this list.
UINT8 numActiveTracks Number of five-char strings
char[5][numActiveTracks] activeTracks List of four-character + terminating null strings ("t0s0 ", "t1s0 ", etc.). This is a list of tracks that will be played in the song. Omitting a track from this list will cause it not to be played. The text here corresponds to the track ID from the header field trackIDs. The order of the tracks in this list does not seem to matter.

0xE7: Track title

This event's data is in the following structure.

Data type Name Description
UINT8 lenTitle Length of track title, including terminating null
char[lenTitle] title Track title, null terminated


There are no known tools that work with files in this format.


This file format was reverse engineered by Malvineous. If you find this information helpful in a project you're working on, please give credit where credit is due. (A link back to this wiki would be nice too!)