The Official MIDI Specifications

General MIDI 2 (GM 2)

General MIDI 1 made great strides in the music industry by providing a platform for compatibility between device manufacturers and content providers. Still, by 1999 many manufacturers were producing sound generators (synthesizers) with far more sounds and more expression capability, so they developed extensions to General MIDI 1 which increased both the number of available sounds and the amount of control available for sound editing and musical performance. All GM 2 devices are also fully compatible with General MIDI 1.

To support new features in GM 2 devices, the MIDI specification was also extended with numerous new control messages, include MIDI Tuning, Controllers, RPNs, and Universal System Exclusive Messages. Of particular significance are the new Universal System Exclusive Messages, including Controller Destination Setting, Key-Based Instrument Controllers, Global Parameter Control, and Master Fine/Coarse Tuning.

GM 2 Specification Update 1.1

In September 2003 a new version of the General MIDI 2 Specification document was made available, reflecting changes to the specification mandated by two new Recommended Practices: RP-036 sets a default Pan Curve for future AMEI/MMA specifications (equivalent to the Pan Curve defined in GML and DLS) and amends GM 2 to include this curve; RP-037 adds a recommendation that GM 2 devices support the MIDI Tuning Extension "Scale/Octave Tuning Real Time One-Byte form" message.

GM 2 Specification Update 1.2

In 2007 Recommend Practice RP-044 was adopted for implementing the Mod Depth Range RPN message on GM 2 devices. This recommendation does not apply to other device specifications (i.e. SP-MIDI) that refer to GM 2. For those devices, the recommended response to Mod Depth Range RPN is either undefined or should be defined in those specifications.

GM 2 Features (Required)

All of the GM 1 Features
Number of Notes:
32 simultaneous notes
MIDI Channels: 16
- Simultaneous Melodic Instruments = up to 16 (all Channels)
- Simultaneous Percussion Kits = up to 2 (Channel 10/11)
Control Change Messages (Some Optional)
- Bank Select (cc#0/32)
- Modulation Depth (cc#1)
- Portamento Time (cc#5)
- Channel Volume (cc#7)
- Pan (cc#10)
- Expression (cc#11)
- Hold1 (Damper) (cc#64)
- Portamento ON/OFF (cc#65)
- Sostenuto (cc#66)
- Soft (cc#67)
- Filter Resonance (Timbre/Harmonic Intensity) (cc#71)
- Release Time (cc#72)
- Attack time (cc#73)
- Brightness (cc#74)
- Decay Time (cc#75) (new message)
- Vibrato Rate (cc#76) (new message)
- Vibrato Depth (cc#77) (new message)
- Vibrato Delay (cc#78) (new message)
- Reverb Send Level (cc#91)
- Chorus Send Level (cc#93)
- Data Entry (cc#6/38)
- RPN LSB/MSB (cc#100/101)
Registered Parameter Numbers
- Pitch Bend Sensitivity
- Channel Fine Tune
- Channel Coarse Tune
- Modulation Depth Range (Vibrato Depth Range)
- RPN NULL
Universal System Exclusive Messages
- Master Volume
- Master Fine Tuning
- Master Coarse Tuning
- Reverb Type
- Reverb Time
- Chorus Type
- Chorus Mod Rate
- Chorus Mod Depth
- Chorus Feedback
- Chorus Send to Reverb
- Controller Destination Setting
- Scale/Octave Tuning Adjust
- Key-Based Instrument Controllers
- GM2 System On
GM 2 Instrument Sound Set
GM 2 Percussion Sound Set

GM 2 Developer Information

Developers of GM 2 compatible devices or content should consult the GM 1 Developer Guidelines for additional recommendations to insure improved compatibility among GM products.


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Related Items

  • General MIDI Logos

    GM Logos are available for MMA Members to use with qualifying compliant products on packaging and marketing materials.