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It's a very simple idea although it's difficult to explain exactly what I mean... If you notice for a moment that there are just two sets of whole note scales, if you imagine a piano where all the white keys are one of those whole note scales and all the black keys is the other... so there is no space without black keys like E-F and B-C... Does anyone know if someone has ever built a piano like this? It seems like it would be interesting.