General Midi is part of the Midi Specification.  It provides an extra level of requirements for how synthesizers should produce sound in response to Midi events, and how Midi file composers should organize their musical arrangements.

The aim is to provide a common platform for distributing data in Midi format, whether as files or real-time transmissions.

Composers can be confident that music designed to comply with the General Midi specification will sound as close as possible to the intended sound when played back on any General Midi compatible synthesizer.

Minimum Capabilities

General Midi covers the minimum capabilities of a synthesizer, which composers can assume to be available on any destination device.  These capabilities are:

• Support for all 16 possible channels.

• Each channel can play more than one note at a time (polyphony).

• Each channel can use any General Midi voice (see below).

• Able to produce at least 24 notes at the same time (shared across the channels).

• Channel 09 (or ch.10 in 1-based numbering) is allocated to key-based percussion (see below).

• Able to generate all sounds at different velocities.

• Support for Modulation Wheel, Channel Volume, Pan Position, Expression, Sustain and Pitch Bend controllers, and a few others also.

General Midi Voices

The General Midi Sound Set defines the 128 voices which must be available to each channel (except the percussion channel).  The exact voice sounds are not prescribed, but they are expected to suit the voice name definitions as shown.

0=Acoustic Grand Piano

1=Bright Acoustic Piano

2=Electric Grand Piano

3=Honky-tonk Piano

4=Rhodes Piano

5=Chorused Piano

6=Harpsichord

7=Clavinet

8=Celesta

9=Glockenspiel

10=Music Box

11=Vibraphone

12=Marimba

13=Xylophone

14=Tubular Bells

15=Dulcimer

16=Hammond Organ

17=Percussive Organ

18=Rock Organ

19=Church Organ

20=Reed Organ

21=Accordion

22=Harmonica

23=Tango Accordion

24=Nylon Guitar

25=Steel Guitar

26=Jazz Guitar

27=Clean Guitar

28=Muted Guitar

29=Overdriven Guitar

30=Distortion Guitar

31=Guitar Harmonics

32=Acoustic Bass

33=Finger Bass

34=Pick Bass

35=Fretless Bass

36=Slap Bass 1

37=Slap Bass 2

38=Synth Bass 1

39=Synth Bass 2

40=Violin

41=Viola

42=Cello

43=Contrabass

44=Tremolo Strings

45=Pizzicato Strings

46=Orchestral Harp

47=Timpani

48=String Ensemble 1

49=String Ensemble 2

50=SynthStrings 1

51=SynthStrings 2

52=Choir Aahs

53=Voice Oohs

54=Synth Voice

55=Orchestra Hit

56=Trumpet

57=Trombone

58=Tuba

59=Muted Trumpet

60=French Horn

61=Brass Section

62=Synth Brass 1

63=Synth Brass 2

64=Soprano Sax

65=Alto Sax

66=Tenor Sax

67=Baritone Sax

68=Oboe

69=English Horn

70=Bassoon

71=Clarinet

72=Piccolo

73=Flute

74=Recorder

75=Pan Flute

76=Bottle Blow

77=Shakuhachi

78=Whistle

79=Ocarina

80=Square Lead

81=Sawtooth Lead

82=Calliope Lead

83=Chiff Lead

84=Charang Lead

85=Voice Lead

86=Fifths Lead

87=Bass + Lead

88=New Age Pad

89=Warm Pad

90=Polysynth Pad

91=Choir Pad

92=Bowed Pad

93=Metallic Pad

94=Halo Pad

95=Sweep Pad

96=Rain FX

97=Soundtrack FX

98=Crystal FX

99=Atmosphere FX

100=Brightness FX

101=Goblins FX

102=Echoes FX

103=Sci-Fi FX

104=Sitar

105=Banjo

106=Shamisen

107=Koto

108=Kalimba

109=Bagpipe

110=Fiddle

111=Shanai

112=Tinkle Bell

113=Agogo

114=Steel Drums

115=Woodblock

116=Taiko Drum

117=Melodic Tom

118=Synth Drum

119=Reverse Cymbal

120=Fret Noise

121=Breath Noise

122=Seashore

123=Bird Tweet

124=Telephone Ring

125=Helicopter

126=Applause

127=Gunshot

General Midi Drums

In General Midi, channel 09 (ch.10 for 1-based numbering) is allocated as the percussion channel.  This means that it does not use voices, but rather has a range of drum sounds, each of which is played in response to a different piano key (or pitch).

The following pitches must be assigned to the following drum sounds in General Midi, where Middle C=60.

35=Acoustic Bass Drum

36=Bass Drum 1

37=Side Stick

38=Acoustic Snare

39=Hand Clap

40=Electric Snare

41=Low Floor Tom

42=Closed Hi-Hat

43=High Floor Tom

44=Pedal Hi-Hat

45=Low Tom

46=Open Hi-Hat

47=Low-Mid Tom

48=Hi-Mid Tom

49=Crash Cymbal 1

50=High Tom

51=Ride Cymbal 1

52=Chinese Cymbal

53=Ride Bell

54=Tambourine

55=Splash Cymbal

56=Cowbell

57=Crash Cymbal 2

58=Vibraslap

59=Ride Cymbal 2

60=Hi Bongo

61=Low Bongo

62=Mute Hi Conga

63=Open Hi Conga

64=Low Conga

65=High Timbale

66=Low Timbale

67=High Agogo

68=Low Agogo

69=Cabasa

70=Maracas

71=Short Whistle

72=Long Whistle

73=Short Guiro

74=Long Guiro

75=Claves

76=Hi Wood Block

77=Low Wood Block

78=Mute Cuica

79=Open Cuica

80=Mute Triangle

81=Open Triangle