Plurry: a scheme for a musical instrument

"Plurry"is my name for an imaginary musical instrument that reveals much about the mathematical basis of music. What makes it different is not the material it is made of - it could be a string or percussive or electronic mechanism - but the spatial arrangement of the tones. They are arranged not in one dimension but two - roughly, octaves and twelfths. If could be a teaching tool. Certain tone-series, which I call plures, would be played on it with simple actions; and the actions for playing in all keys would be the same. One reader built a prototype and was enthusiastic about its ease of playing.