In the beginning was MIDI. Later came General MIDI, which standardized 128 patches (sounds) as well as certain other features to encourage compatibility among musical equipment manufactureres. Both include 16 possible channels of information. Channels can have instrument assignments as well as note and other values. MIDI itself has been around for years and is fairly standardized but the channel assignments are not. One composer may use channel 1 for a piano sound and channel 2 for a bass sound while another composer may use completely differend sounds on those channels. General MIDI pieces typically use Channel 10 for drums or percussion but that is not absolutely required. That's probably why it appears "wildly non-standard."

Before they made me they broke the mold!
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