General MIDI Level 2

General MIDI Level 2 or GM2 is a specification for synthesizers which defines several requirements beyond the more abstract MIDI standard and is based on General MIDI and GS extensions. It was adopted in 1999 by the MIDI Manufacturers Association (MMA).

General MIDI 2 compatible synthesizers access all of the 256 instruments by setting cc#0 (Bank Select MSB) to 121 and using cc#32 (Bank Select LSB) to select the variation bank before a Program Change. Variation bank 0 contains full GM sound set.

These are the same patch numbers as defined in the original version of GS. Drum bank is accessed by setting cc#0 (Bank Select MSB) to 120 and cc#32 (Bank Select LSB) to 0 and PC (Program Change) to select drum kit.

These are the same GS drum notes and span Drum Kits 1 to 49:

(Some messages are optional)

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