  We present an algebraic construction of music notes and show how to associate
them inseveral ways to construct music ranges. Then a family of ranges emerge
with a fixed number of notes: two, three, five, seven, twelve, seventeen, etc.
A classification of these scales is simple with the concept of multiplicative
structure. The action of such a multiplicative structure on a music note
introduces the definition of tonality. Multiplicative structure classification
is then straightforward with the notions of type and mode. We detail the case
of music scales with five and seven notes and propose musical examples for a
wide range of modes.
