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midi_file_format

MIDI File Format

License

The bulk of information for this article comes from public domain sources, in particular Standard MIDI File Format by Dustin Caldwell. The rest was filled in through various sources and contributions. As such, even though most articles on this site are licensed under the Creative Commons Attribution license, this article is here by released into the public domain.

File Structure

MIDI sequence files are made up of chunks of data. The header chunk describes information about the MIDI file as a whole. The header chunk is followed by one or more track chunks, each of which contain a sequence of MIDI events. MIDI events consist of some kind of command or status with associated data plus a time-stamp for each message. Each track may contain information for up to 16 MIDI channels. Events and data are stored big-endian which is the most significant byte first. Events are stored in a variable-length format which may use one or more bytes. The high-order bit is used to determine the last byte in a sequence. If the high-order bit is set to 1 then another byte follows, if the high-order bit is 0 then this is the last byte in the sequence. The lower 7 bits of each byte are used to store the actual data. As the commands are read the data must be reformatted for the specific platform.

Header Chunk

The first chunk in the file is the header chunk. The header chunk always starts with a magic value 'MThd'. This is stored in the first 4 bytes of the file. The next four bytes is the size of the header in bytes. This size does not count the magic value or the size field of the header. As such, this value will always be 6.

4D 54 68 64 00 00 00 06 ff ff nn nn dd dd

Following the size field is a 16-bit field specifying the file format (ff ff above). This will be one of three values:

0 - single-track
1 - multiple tracks, synchronous
2 - multiple tracks, asynchronous

Single track is only one track that contains all of the MIDI events for the entire file, including the song title, time signature, tempo and music events. Synchronous multiple tracks contains more than one track each of which start at the same time. The first track typically contains song information such as the title and copyright information, time signature, tempo, etc. The following tracks contain a title, musical event data, etc. specific to that track. Asynchronous multiple tracks also contains multiple tracks however they do not have to start at the same time.

The next field is a 16-bit value specifying the number of tracks in the file (nn nn above). For single-track this value is 1. For multiple track files this can be up to 65535.

The last field is a 16-bit value specifying the number of delta-time ticks per quarter note (dd dd above) or frames per second. If the most significant bit is 0 the remaining bits specify the delta-time ticks per beat. If the most significant bit is 1 the remaining bits specify the delta-time in frames per second. For ticks per beat, common values range from 48 to 960.

Frames per second is defined by breaking the remaining 15 bits into two values. The top 7 bits define a value for the number of SMPTE frames and can be 24, 25, 29 (for 29.97 fps) or 30. The remaining 8 bits define how many ticks there are per frame.

In C the header structure looks something like this:

#define MID_ID		'dhTM'
#define MID_HDR_SIZE	0x06000000
 
#define MID_FMT_SINGLE	0x0000	// single track
#define MID_FMT_MULTIS	0x0100	// multiple tracks, synchronous
#define MID_FMT_MULTIA	0x0200	// multiple tracks, asynchronous
 
#pragma pack(push, 1)
 
struct mid_header {
	unsigned int	id;	// identifier "MThd"
	unsigned int	size;	// always 6 in big-endian format
	unsigned short	format;	// big-endian format
	unsigned short  tracks;	// number of tracks, big-endian
	unsigned short	ticks;	// number of ticks per quarter note, big-endian
};
 
#pragma pack(pop)

Track Chunks

Following the header is one or more track chunks. Each track has one header followed by a stream of MIDI event. Similar to the file header, the track header always starts with a magic value 'MTrk'. This is stored in the first 4 bytes of the track header. The next four bytes is the size of the size of the track in bytes. This size does not count the magic value or the size field of the header.

4D 54 72 6B xx xx xx xx

In C the header structure looks something like this:

#define MID_TRK_ID	'krTM'
 
struct mid_track {
	unsigned int	id;	// identifier "MTrk"
	unsigned int	length;	// track length, big-endian
};

Following the header are the actual MIDI events. MIDI events consist of a delta-time followed by a MIDI event. The delta-time is the number of ticks after which the MIDI event should be executed. The delta-time is a variable length encoded value. Each byte of the value contains 7 bits of data and 1 bit for continuation. The first byte is read and the 7 least significant bits are extracted. If the most significant bit is 1, the next byte is read. The 7 least significant bits are extracted. The previous value is multiplied by 128 and the new value is added. If the most significant bit is 0, the process is done. The delta-time should never be more than 4 bytes long.

The delta-time is relative to the last event. If two or more events should be executed simultaneously, the first event specifies the delta-time to wait since the previous event, the following events have a delta-time of 0. Simply put, wait 0 ticks from the previous event to execute this event.

Example:

Play note A followed by note B 100 ticks later, stop A after 200 ticks, stop B at the same time as A.

Ticks     Event              Description
--------------------------------------------------------------
0         Note A on event    Note A starts playing immediately
100       Note B on event    Note B starts playing 100 ticks after A
100       Note A off event   Note A stops playing after 200 total ticks
0         Note B off event   Note B stops at the same time as A (after 100 ticks)

MIDI Event Commands

Each midi event has a command byte followed by one or more data bytes. The command byte will always have a most significant bit of 1. Each command has different parameters and lengths, but the data that follows the command will have a most significant bit of 0. The exception to this is a meta-event, which may contain data with a most significant bit of 1. However, meta-events require a length parameter which alleviates confusion.

For all of these messages, a convention called the "running status byte" or "running mode" may be used. If the transmitter wishes to send another message of the same type on the same channel, thus the same status byte, the status byte need not be resent. Running mode is identified by checking the most significant bit of the next "event byte". If the most significant bit is 0, the "event byte" is not really the next event but the first parameter to the event. The actual event byte was omitted and the previous event byte is used.

+--7----6----5----4----3----2----1----0-+
|  1 |  Event type  |  Channel number   |
+---------------------------------------+

Each command byte has 2 parts. The left nibble (4 bits) contains the actual command, and the right nibble (xxxx) contains the midi channel number on which the command will be executed. There are 16 midi channels and 8 midi commands. The data bytes that follow the command will have a most significant bit of 0.

Hex Binary Data Description
8x 1000xxxx nn vv Note off event. This message is sent when a note is released (ended).

nn = note number
vv = velocity
9x 1001xxxx nn vv Note on event. This message is sent when a note is depressed (start). A "note on" event with a velocity of zero is equivalent to a "note off" event.

nn = note number
vv = velocity
Ax 1010xxxx nn vv Polyphonic Key Pressure (After-touch). This message is sent when the pressure (velocity) of a previously triggered note changes.

nn = note number
vv = velocity
Bx 1011xxxx cc vv This message is sent when a controller value changes. Controllers include devices such as pedals and levers. Certain controller numbers are reserved for specific purposes. See Channel Mode Messages.

cc = controller number
vv = new value
Cx 1100xxxx pp Program (patch) change. This message sent when the patch number changes.
pp = new program number
Dx 1101xxxx cc Channel Pressure (After-touch). This message is sent when the channel pressure changes. Some velocity-sensing keyboards do not support polyphonic after-touch. Use this message to send the single greatest velocity.

cc = channel number
Ex 1110xxxx bb tt Pitch wheel change. This message is sent to indicate a change in the pitch wheel. The pitch wheel is measured by a fourteen bit value. Center (no pitch change) is 2000H. Sensitivity is a function of the transmitter.

bb = bottom (least sig) 7 bits of value
tt = top (most sig) 7 bits of value
FF 11111111 xx nn dd .. Meta-event. This message indicates a meta-event which is described below.

Channel Mode Messages

Hex Binary Data Description
Bx 1011xxxx cc vv This the same code as the Control Change (above), but implements Mode control by using reserved controller numbers. The numbers are:

Local Control.
When Local Control is Off, all devices on a given channel will respond only to data received over MIDI. Played data, etc. will be ignored. Local Control On restores the functions of the normal controllers.

cc = 122, vv = 0: Local Control Off
cc = 122, vv = 127: Local Control On

All Notes Off.
When an All Notes Off is received, all oscillators will turn off.

cc = 123, vv = 0: All Notes Off

(See text for description of actual mode commands.)
cc = 124, vv = 0: Omni Mode Off
cc = 125, vv = 0: Omni Mode On
cc = 126, vv = M: Mono Mode On (Poly Off) where M is the number of channels (Omni Off) or 0 (Omni On)
cc = 127, vv = 0: Poly Mode On (Mono Off)
(Note: These four messages also cause All Notes Off)

Meta-Events

The following table lists meta-events which have no midi channel number. They are of the format:

FF xx nn dd

All meta-events start with FF followed by the command (xx), the length, or number of bytes that will contain data (nn), and the actual data (dd).

Hex Binary Data Description
00 00000000 nn ssss Sets the track's sequence number

nn = 02 (length of 2-byte sequence number).
ssss = sequence number
01 00000001 nn tt … Text event - any text you want.

nn = length in bytes of text.
tt = text characters
02 00000010 nn tt … Same as text event, but used for copyright info.

nn tt = same as text event.
03 00000011 nn tt … Sequence or Track name.

nn tt = same as text event.
04 00000100 nn tt … Track instrument name.

nn tt = same as text event.
05 00000101 nn tt … Lyric. Defines the lyrics in a song by syllable or group of words per quarter note.

nn tt = same as text event.
06 00000110 nn tt … Marker. Marks a significant point in time for the sequence (e.g. beginning of a new verse).

nn tt = same as text event.
07 00000111 nn tt … Cue point. Marks the start of some type of new sound or action.

nn tt = same as text event.
20 00100000 ?? MIDI channel prefix assignment.
21 00100001 01 pp Has been used, though unofficially, for a MIDI port or cable number. (deprecated)
2F 00101111 00 End of Track. This event must come at the end of each track.
51 01010001 03 tttttt Set tempo

tttttt = microseconds/quarter note. (microseconds/beat)

MICROSECONDS_PER_MINUTE = 60000000

BPM = MICROSECONDS_PER_MINUTE / MPQN
MPQN = MICROSECONDS_PER_MINUTE / BPM

If no tempo is specified, the default is 120 beats-per-minute. (500,000 microseconds/beat)

TODO: How does this relate to delta-time ticks per quarter note specified in the header chunk?
54 01010100 05 hh mm ss ff sf SMPTE offset. SMPTE starting point from the beginning of the track. hh = hours (0-23), mm = minutes (0-59), ss = seconds (0-59), ff = frames (0-30) and sf = sub-frames (0-99) (always 100 sub-frames per frame, no matter what sub-division is specified in the MIDI header chunk).

The byte used to specify the hour offset also specifies the frame rate in the following format: 0rrhhhhh where rr is two bits for the frame rate where 00 = 24 fps, 01 = 25 fps, 10 = 30 fps (drop frame), 11 = 30 fps and hhhhh is 5 bits for the hour (0-23). The hour byte's top bit is always 0. The frame byte's possible range depends on the encoded frame rate in the hour byte. A 25 fps frame rate means that a maximum value of 24 may be set for the frame byte.
58 01011000 04 nn dd cc bb Time Signature

nn = numerator of time sig.
dd = denominator of time sig. 2 = quarter 3 = eighth, etc.
cc = number of MIDI clocks in metronome click. (MIDI clocks per beat)
bb = number of 32nd notes to the quarter note

MIDI clock bytes are used to synchronize playback of multiple MIDI devices. The MIDI clock ticks 24 times per quarter note. For example, 6/8 time with a metronome click every 3 eighth notes and 24 clocks per quarter note, the cc value would be set to 36 MIDI clocks per beat.
59 01011001 02 sf mi Key signature

sf = sharps/flats (-7 = 7 flats, 0 = key of C, 7 = 7 sharps).
mi = major/minor (0 = major, 1 = minor)
7F 01111111 xx dd … Sequencer specific information

xx = number of bytes to be sent.
dd = data
  bpm = beats per minute.
  60000000 / bpm = tt tt tt.
  
  nn = delta-time ticks per beat. (specified in the header chunk)
  tt tt tt = microseconds per beat. (specified by the tempo event)
  tt tt tt / nn = microseconds per delta-time tick. (PPQN Clock)
  
  96 delta-time ticks per beat. (header)
  120 beats per minute = 500000 microseconds per beat. (tempo event)
  500000 / 96 = 5208.3 microseconds per delta-time tick.
  
  500000 / 48 = 10416.7 microseconds per delta-time tick.

System Messages

The following are system messages which control the entire system. These commands are used to control physical MIDI devices and are not typically found in MIDI files. They have no midi channel number. (They will generally only apply to controlling a midi keyboard, etc.)

System Common Messages

Hex Binary Data Description
F0 11110000 ii dd … dd F7 System Exclusive. This message makes up for all that MIDI doesn't support. (ii) is a seven bit Manufacturer's I.D. code. If the synthesizer recognizes the I.D. code as its own, it will listen to the rest of the message (dd). Otherwise, the message will be ignored. System Exclusive is used to send bulk dumps such as patch parameters and other non-spec data. (Note: Real-Time messages ONLY may be interleaved with a System Exclusive.)
F1 11110001 Undefined.
F2 11110010 ll mm Song Position Pointer. This is an internal 14 bit register that holds the number of MIDI beats (1 beat = six MIDI clocks) since the start of the song. ll is the least significant byte, mm the most significant byte.
F3 11110011 ss Song Select. The Song Select specifies which sequence or song is to be played. ss is the song number.
F4 11110100 Undefined.
F5 11110101 Undefined.
F6 11110110 Tune Request. Upon receiving a Tune Request, all analog synthesizers should tune their oscillators.
F7 11110111 End of Exclusive. Used to terminate a System Exclusive dump (see above).

Divided System Exclusive Events

A large amount of System Exclusive data in a Normal System Exclusive Event could cause following MIDI Channel Events to be transmitted after the time they should be played. This will cause an unwanted delay in play back of the following events. The second type of System Exclusive Events solve this problem by allowing a large amount of System Exclusive data to be divided into smaller blocks, transmitted with a delay between each division to allow the transmission of other MIDI events in order to prevent congesting of the limited MIDI bandwidth. The initial Divided System Exclusive Event follows the same format as a Normal System Exclusive Event with the exception that the last data byte is not 0xF7. This indicates the the System Exclusive data is not finished and will be continued in an upcoming Divided System Exclusive Event. Any following Divided System Exclusive Events before the final one use the a similar format as the first, only the start byte is 0xF7 instead of 0xF0 to signal continuation of System Exclusive data. The final block follows the same format as the continuation blocks, except the last data byte is 0xF7 to signal the completion of the divided System Exclusive data.

Authorization System Exclusive Events

The last type of System Exclusive Event authorizes and enables the transmission of special messages such as Song Position Pointer, MIDI Time Code and Song Select messages. These System Exclusive Events use the event type value 0xF7.

System Real-Time Messages

Hex Binary Data Description
F8 11111000 Timing clock used when synchronization is required. Sent 24 times per quarter note when synchronization is required (see text).
F9 11111001 Undefined.
FA 11111010 Start the current sequence playing. (This message will be followed with Timing Clocks).
FB 11111011 Continue at the point the sequence was stopped.
FC 11111100 Stop the current sequence.
FD 11111101 Undefined.
FE 11111110 Active Sensing. Use of this message is optional. When initially sent, the receiver will expect to receive another Active Sensing message each 300ms (max), or it will be assume that the connection has been terminated. At termination, the receiver will turn off all voices and return to normal (non-active sensing) operation.
FF 11111111 Reset. In terms of MIDI devices, this command is to reset all receivers in the system to power-up status. This should be used sparingly, preferably under manual control. In particular, it should not be sent on power-up. The MIDI file format redefines this command for meta-events as described above.

Controller Codes

This table lists the controller codes used in the controller setting change command above.

Hex Decimal Description
00 0 Bank Select (Controller # 32 more commonly used) 0-127 MSB
01 1 Modulation Wheel 0-127 MSB
02 2 Breath Controller 0-127 MSB
03 3 Continuous Controller #3 0-127 MSB
04 4 Foot Controller 0-127 MSB
05 5 Portamento Time 0-127 MSB
06 6 Data Entry MSB 0-127 MSB
07 7 Main Volume 0-127 MSB
08 8 Balance 0-127 MSB
09 9 Continuous controller #9 0-127 MSB
0A 10 Pan 0-127 MSB
0B 11 Expression Controller 0-127 MSB
0C 12 Effect Control 1 0-127 MSB
0D 13 Effect Control 2 0-127 MSB
0E 14 Continuous controller #14 0-127 MSB
0F 15 Continuous controller #15 0-127 MSB
10 16 General Purpose Controllers (No. 1) 0-127 MSB
11 17 General Purpose Controllers (No. 2) 0-127 MSB
12 18 General Purpose Controllers (No. 3) 0-127 MSB
13 19 General Purpose Controllers (No. 4) 0-127 MSB
14 20 Continuous controller #20 0-127 MSB
15 21 Continuous controller #21 0-127 MSB
16 22 Continuous controller #22 0-127 MSB
17 23 Continuous controller #23 0-127 MSB
18 24 Continuous controller #24 0-127 MSB
19 25 Continuous controller #25 0-127 MSB
1A 26 Continuous controller #26 0-127 MSB
1B 27 Continuous controller #27 0-127 MSB
1C 28 Continuous controller #28 0-127 MSB
1D 29 Continuous controller #29 0-127 MSB
1E 30 Continuous controller #30 0-127 MSB
1F 31 Continuous controller #31 0-127 MSB
20 32 Bank Select 0-127 LSB
21 33 Modulation Wheel 0-127 LSB
22 34 Breath Controller 0-127 LSB
23 35 Continuous controller #3 0-127 LSB
24 36 Foot Controller 0-127 LSB
25 37 Portamento Time 0-127 LSB
26 38 Data Entry LSB 0-127 LSB
27 39 Main Volume 0-127 LSB
28 40 Balance 0-127 LSB
29 41 Continuous controller #9 0-127 LSB
2A 42 Pan 0-127 LSB
2B 43 Expression Controller 0-127 LSB
2C 44 Effect Control 1 0-127 LSB
2D 45 Effect Control 2 0-127 LSB
2E 46 Continuous controller #14 0-127 LSB
2F 47 Continuous controller #15 0-127 LSB
30 48 General Purpose Controllers (No. 1) 0-127 LSB
31 49 General Purpose Controllers (No. 2) 0-127 LSB
32 50 General Purpose Controllers (No. 3) 0-127 LSB
33 51 General Purpose Controllers (No. 4) 0-127 LSB
34 52 Continuous controller #20 0-127 LSB
35 53 Continuous controller #21 0-127 LSB
36 54 Continuous controller #22 0-127 LSB
37 55 Continuous controller #23 0-127 LSB
38 56 Continuous controller #24 0-127 LSB
39 57 Continuous controller #25 0-127 LSB
3A 58 Continuous controller #26 0-127 LSB
3B 59 Continuous controller #27 0-127 LSB
3C 60 Continuous controller #28 0-127 LSB
3D 61 Continuous controller #29 0-127 LSB
3E 62 Continuous controller #30 0-127 LSB
3F 63 Continuous controller #31 0-127 LSB
40 64 Damper pedal on/off (Sustain) 0=off 127=on
41 65 Portamento on/off 0=off 127=on
42 66 Sustenuto on/off 0=off 127=on
43 67 Soft Pedal on/off 0=off 127=on
44 68 Legato Footswitch on/off 0=off 127=on
45 69 Hold 2 on/off 0=off 127=on
46 70 Sound Controller 1 (default: Sound Variation) on/off 0=off 127=on
47 71 Sound Controller 2 (default: Timbre/Harmonic Content) on/off 0=off 127=on
48 72 Sound Controller 3 (default: Release Time) on/off 0=off 127=on
49 73 Sound Controller 4 (default: Attack Time) on/off 0=off 127=on
4A 74 Sound Controller 5 (default: Brightness) on/off 0=off 127=on
4B 75 Sound Controller 6 (no defaults) on/off 0=off 127=on
4C 76 Sound Controller 7 (no defaults) on/off 0=off 127=on
4D 77 Sound Controller 8 (no defaults) on/off 0=off 127=on
4E 78 Sound Controller 9 (no defaults) on/off 0=off 127=on
4F 79 Sound Controller 10 (no defaults) on/off 0=off 127=on
50 80 General Purpose Controllers (No. 5) on/off 0=off 127=on
51 81 General Purpose Controllers (No. 6) on/off 0=off 127=on
52 82 General Purpose Controllers (No. 7) on/off 0=off 127=on
53 83 General Purpose Controllers (No. 8) on/off 0=off 127=on
54 84 Portamento Control on/off 0=off 127=on
55 85 Undefined on/off 0=off 127=on
56 86 Undefined on/off 0=off 127=on
57 87 Undefined on/off 0=off 127=on
58 88 Undefined on/off 0=off 127=on
59 89 Undefined on/off 0=off 127=on
5A 90 Undefined on/off 0=off 127=on
5B 91 Effects 1 Depth (previously External Effects Depth) on/off 0=off 127=on
5C 92 Effects 2 Depth (previously Tremolo Depth) on/off 0=off 127=on
5D 93 Effects 3 Depth (previously Chorus Depth) on/off 0=off 127=on
5E 94 Effects 4 Depth (previously Celeste Detune Depth) on/off 0=off 127=on
5F 95 Effects 5 Depth (previously Phaser Depth) on/off 0=off 127=on
60 96 Data Entry Increment (+1) 127
61 97 Data Entry Decrement (-1) 127
62 98 Non-Registered Parameter Number LSB ?
63 99 Non-Registered Parameter Number MSB ?
64 100 Registered Parameter Number LSB ?
65 101 Registered Parameter Number MSB ?
66 102 Undefined ?
67 103 Undefined ?
68 104 Undefined ?
69 105 Undefined ?
6A 106 Undefined ?
6B 107 Undefined ?
6C 108 Undefined ?
6D 109 Undefined ?
6E 110 Undefined ?
6F 111 Undefined ?
70 112 Undefined ?
71 113 Undefined ?
72 114 Undefined ?
73 115 Undefined ?
74 116 Undefined ?
75 117 Undefined ?
76 118 Undefined ?
77 119 Undefined ?
78 120 Undefined ?
79 121 Reset All Controllers ?
7A 122 Local Control on/off 0=off 127=on
7B 123 All Notes Off (!!) 0
7C 124 Omni Mode Off (includes all notes off) 0
7D 125 Omni mode On (includes all notes off) 0
7E 126 Mono On (Poly Off)(includes all notes off) *
7F 127 Poly On (Mono Off)(includes all notes off) 0

*Note: This equals the number of channels, or zero if the number of channels equals the number of voices in the receiver.

Note Index

The following table lists the numbers corresponding to notes for use in note on and note off commands.

Octave Notes
C C# D D# E F F# G G# A A# B
0 0 1 2 3 4 5 6 7 8 9 10 11
1 12 13 14 15 16 17 18 19 20 21 22 23
2 24 25 26 27 28 29 30 31 32 33 34 35
3 36 37 38 39 40 41 42 43 44 45 46 47
4 48 49 50 51 52 53 54 55 56 57 58 59
5 60 61 62 63 64 65 66 67 68 69 70 71
6 72 73 74 75 76 77 78 79 80 81 82 83
7 84 85 86 87 88 89 90 91 92 93 94 95
8 96 97 98 99 100 101 102 103 104 105 106 107
9 108 109 110 111 112 113 114 115 116 117 118 119
10 120 121 122 123 124 125 126 127

General MIDI Instrument Patch Map

The heart of General MIDI (GM) is the Instrument Patch Map This is a list of 128 sounds, with corresponding MIDI program numbers. Most of these are imitative sounds, though the list includes synth sounds, ethnic instruments and a handful of sound effects.

The sounds fall roughly into sixteen families of eight variations each. Grouping sounds makes it easy to re-orchestrate a piece using similar sounds. The instrument map isn't the final word on musical instruments of the world, but it's pretty complete.

Prog# Instrument Prog# Instrument
(0-7 Piano) (8-15 Chrome Percussion)
0 Acoustic Grand 8 Celesta
1 Bright Acoustic 9 Glockenspiel
2 Electric Grand 10 Music Box
3 Honky-Tonk 11 Vibraphone
4 Electric Piano 1 12 Marimba
5 Electric Piano 2 13 Xylophone
6 Harpsichord 14 Tubular Bells
7 Clav 15 Dulcimer
(16-23 Organ) (24-31 Guitar)
16 Drawbar Organ 24 Acoustic Guitar(nylon)
17 Percussive Organ 25 Acoustic Guitar(steel)
18 Rock Organ 26 Electric Guitar(jazz)
19 Church Organ 27 Electric Guitar(clean)
20 Reed Organ 28 Electric Guitar(muted)
21 Accoridan 29 Overdriven Guitar
22 Harmonica 30 Distortion Guitar
23 Tango Accordian 31 Guitar Harmonics
(32-39 Bass) (40-47 Strings)
32 Acoustic Bass 40 Violin
33 Electric Bass(finger) 41 Viola
34 Electric Bass(pick) 42 Cello
35 Fretless Bass 43 Contrabass
36 Slap Bass 1 44 Tremolo Strings
37 Slap Bass 2 45 Pizzicato Strings
38 Synth Bass 1 46 Orchestral Strings
39 Synth Bass 2 47 Timpani
(48-55 Ensemble) (56-63 Brass)
48 String Ensemble 1 56 Trumpet
49 String Ensemble 2 57 Trombone
50 SynthStrings 1 58 Tuba
51 SynthStrings 2 59 Muted Trumpet
52 Choir Aahs 60 French Horn
53 Voice Oohs 61 Brass Section
54 Synth Voice 62 SynthBrass 1
55 Orchestra Hit 63 SynthBrass 2
(64-71 Reed) (72-79 Pipe)
64 Soprano Sax 72 Piccolo
65 Alto Sax 73 Flute
66 Tenor Sax 74 Recorder
67 Baritone Sax 75 Pan Flute
68 Oboe 76 Blown Bottle
69 English Horn 77 Skakuhachi
70 Bassoon 78 Whistle
71 Clarinet 79 Ocarina
(80-87 Synth Lead) (88-95 Synth Pad)
80 Lead 1 (square) 88 Pad 1 (new age)
81 Lead 2 (sawtooth) 89 Pad 2 (warm)
82 Lead 3 (calliope) 90 Pad 3 (polysynth)
83 Lead 4 (chiff) 91 Pad 4 (choir)
84 Lead 5 (charang) 92 Pad 5 (bowed)
85 Lead 6 (voice) 93 Pad 6 (metallic)
86 Lead 7 (fifths) 94 Pad 7 (halo)
87 Lead 8 (bass+lead) 95 Pad 8 (sweep)
(96-103 Synth Effects) (104-110 Ethnic)
96 FX 1 (rain) 104 Sitar
97 FX 2 (soundtrack) 105 Banjo
98 FX 3 (crystal) 106 Shamisen
99 FX 4 (atmosphere) 107 Koto
100 FX 5 (brightness) 108 Kalimba
101 FX 6 (goblins) 109 Bagpipe
102 FX 7 (echoes) 110 Fiddle
103 FX 8 (sci-fi) 111 Shanai
(112-119 Percussive) (120-127 Sound Effects)
112 Tinkle Bell 120 Guitar Fret Noise
113 Agogo 121 Breath Noise
114 Steel Drums 122 Seashore
115 Woodblock 123 Bird Tweet
116 Taiko Drum 124 Telephone Ring
117 Melodic Tom 125 Helicopter
118 Synth Drum 126 Applause
119 Reverse Cymbal 127 Gunshot

General MIDI Percussion Key Map

General MIDI also includes a Percusssion Key Map. This mapping derives from the Roland/Sequential mapping used on early drum machines. As with the Instrument Map, it doesn't cover every percussive instrument in the world, but it's more than adequate as a basic set.

To avoid concerns with channels, GM restricts percussion to MIDI Channel 9. Theoretically, the lower nine channels (0 - 8) are for the instruments, but the GM spec states that a sound module must respond to all sixteen MIDI channels, with dynamic voice allocation and a minimum of 24 voices.

MIDI key Drum Sound MIDI key Drum Sound
35 Acoustic Bass Drum 59 Ride Cymbal 2
36 Bass Drum 1 60 Hi Bongo
37 Side Stick 61 Low Bongo
38 Acoustic Snare 62 Mute Hi Conga
39 Hand Clap 63 Open Hi Conga
40 Electric Snare 64 Low Conga
41 Low Floor Tom 65 High Timbale
42 Closed Hi-Hat 66 Low Timbale
43 High Floor Tom 67 High Agogo
44 Pedal Hi-Hat 68 Low Agogo
45 Low Tom 69 Cabasa
46 Open Hi-Hat 70 Maracas
47 Low-Mid Tom 71 Short Whistle
48 Hi-Mid Tom 72 Long Whistle
49 Crash Cymbal 1 73 Short Guiro
50 High Tom 74 Long Guiro
51 Ride Cymbal 1 75 Claves
52 Chinese Cymbal 76 Hi Wood Block
53 Ride Bell 77 Low Wood Block
54 Tambourine 78 Mute Cuica
55 Splash Cymbal 79 Open Cuica
56 Cowbell 80 Mute Triangle
57 Crash Cymbal 2 81 Open Triangle
58 Vibraslap

Sources

More Information

midi_file_format.txt · Last modified: 2016/05/14 11:04 (external edit)