in 1991. The official specification is available in English from the MMA, bound together with the MIDI 1.0 specification, and in Japanese from the Association of Musical Electronic Industry (AMEI).

GM imposes several requirements beyond the more abstract MIDI 1.0 specification. While MIDI 1.0 by itself provides a communication protocol which ensures that different instruments can interoperate at a fundamental level - for example, that pressing keys on a MIDI keyboard will cause an attached