An important thing to remember about MIDI (Musical Instrument Digital Interface) is that it contains no sound. Rather it is a way of allowing one musical instrument to 'speak' to another. This is usually done in a MIDI 'chain' in which instruments (and possibly a computer) are linked together using cable. One instrument is designated the controller, and the MIDI signal triggers events on the various instruments in the chain. This can be done live in real time, or using a prepared sequence (usually made on a computer). By chaining together several sound modules in this way, an enormous palette of effects and sounds (including orchestral instrument sounds) become available to the user.

MIDI works by recording events such as 'note on' (the trigger) and 'note off' (the release) and numerous other controller events that occur in between those two (and indeed after the last). Although any number of sounds or timbres may be available to a MIDI instrument, usually they are identified by the numbers 0-127 (or 1 -128 on some machines). There are normally 16 MIDI channels open at any one time, so signals may be transmitted to any of the 128 available timbres using program change messages. Assuming the attached instruments have polyphonic capability, this means 16 simultaneous 'voices' containing potentially limitless timbres.

General MIDI was the result of an agreement between instrument manufacturers to standardise 128 MIDI instrument sounds. Thus, a program change message of 1 will deliver an Acoustic Piano sound on any GM instrument, regardless of manufacturer (although each manufacturer will have their own version of an acoustic piano sound!). See a list of General MIDI sounds below. You will notice that the percussion set is treated separately. This is because each percussion sound is triggered by a single note on a MIDI keyboard, whereas all the other sounds play back across the entire range of a keyboard.

MIDI messages may be triggered by anything, which has made MIDI a useful tool for live performance. As well as the familiar keyboards, there are wind controllers, breath and voice controllers, MIDI percussion, and even light beams and laser controllers. It is not necessary to use GM sounds and any sampler or other instrument attached to a controller can be programmed to emit sounds in response to a MIDI control message.

General MIDI

 1. Acoustic Grand Piano
2. Bright Acoustic Piano
3. Electric Grand Piano
4. Honky-tonk Piano
5. Electric Piano 1
6. Electric Piano 2
7. Harpsichord
8. Clavi

33. Acoustic Bass
34. Electric Bass (finger)
35. Electric Bass (pick)
36. Fretless Bass
37. Slap Bass 1
38. Slap Bass 2
39. Synth Bass 1
40. Synth Bass 2

65. Soprano Sax
66. Alto Sax
67. Tenor Sax
68. Baritone Sax
69. Oboe
70. English Horn
71. Bassoon
72. Clarinet

97. FX 1 (rain)
98. FX 2 (soundtrack)
99. FX 3 (crystal)
100. FX 4 (atmosphere)
101. FX 5 (brightness)
102. FX 6 (goblins)
103. FX 7 (echoes)
104. FX 8 (sci-fi)

  9. Celesta
10. Glockenspiel
11. Music Box
12. Vibraphone
13. Marimba
14. Xylophone
15. Tubular Bells
16. Dulcimer

41. Violin
42. Viola
43. Cello
44. Contrabass
45. Tremelo Strings
46. Pizzicato Strings
47. Orchestral Harp
48. Timpani

 73. Piccolo
74. Flute
75. Recorder
76. Pan Flute
77. Blown Bottle
78. Shakuhachi
79. Whistle
80. Ocarina

 105. Sitar
106. Banjo
107. Shamisen
108. Koto
109. Kalimba
110. Bag Pipe
111. Fiddle
112. Shanai

 17. Drawbar Organ
18. Percussive Organ
19. Rock Organ
20. Church Organ
21. Reed Organ
22. Accordian
23. Harmonica
24. Tango Accordian

 49. String Ensemble
50. String Ensemble
51. SynthStrings 1
52. SynthStrings 2
53. Choir Aahs
54. Voice Oohs
55. Synth Voice
56. Orchestra Hit

 81. Lead 1 (square)
82. Lead 2 (sawtooth)
83. Lead 3 (calliope)
84. Lead 4 (chiff)
85. Lead 5 (charang)
86. Lead 6 (voice)
87. Lead 7 (fifths)
88. Lead 8 (bass + lead)

 113. Tinkle Bell
114. Agogo
115. Steel Drums
116. Woodblock
117. Taiko Drum
118. Melodic Tom
119. Synth Drum
120. Reverse Cymbal

 25. Acoustic Guitar (nylon)
26. Acoustic Guitar (steel)
27. Electric Guitar (jazz)
28. Electric Guitar (clean)
29. Electric Guitar (muted)
30. Overdriven Guitar
31. Distortion Guitar
32. Guitar Harmonics

 57. Trumpet
58. Trombone
59. Tuba
60. Muted Trumpet
61. French Horn
62. Brass Section
63. SynthBrass 1
64. SynthBrass 2

 89. Pad 1 (new age)
90. Pad 2 (warm)
91. Pad 3 (polysynth)
92. Pad 4 (choir)
93. Pad 5 (bowed)
94. Pad 6 (metallic)
95. Pad 7 (halo)
96. Pad 8 (sweep)

 121. Guitar Fret Noise
122. Breath Noise
123. Seashore
124. Bird Tweet
125. Telephone Ring
126. Helicopter
127. Applause
128. Gunshot  
 
 GENERAL MIDI PERCUSSION SET
 
 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


The Orchestra: A User's Manual is a free resource and will remain so. It still receives between 8,000 and 16,000 unique visits per month from all over the world. See the testimonials. Thanks to all the donations, I have been able to create this responsive re-design. But the movies and sound clips recorded in 2004 do show their age. I would really like to re-record everything and add many more techniques, especially for solo and ensemble writing. I estimate this will cost around £30,000. If you know a source of such funds, please contact me: a.hugill [at] bathspa.ac.uk