Don't know if the work of the Midi Association at midi.org has been mentioned before?...
Midi.org
[quote from their site]
The MIDI Association is a free non-profit, member community of people that create music and art with MIDI
Connect – Learn – Create!
Enjoy “all access” to videos, guides, articles, and discussion forums offering tools, tips, and tricks to help you learn everything from MIDI basics to advanced techniques.. Get inspired, get excited, and create your own artistic path. We’re dedicated to helping you get the most out of MIDI.
It’s Free !
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