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[Isaiah Odhner]

Like I've done in Tri-Chromatic Keyboard

I think this would be really helpful, especially for a physical instrument (as opposed to something virtually no one in the world (including me) has a physical analog to), because you could learn from it and apply it back to the real world. I guess there are charts for this sort of thing, but... hm, looking at google images, it's pretty overwhelming. The least overwhelming one is a photo of a guitar with some circles with note names added.