Hi M.Ted
    Sorry if my post came over a bit brusque I was a bit pushed for time.
I don't disagree with you that we generally discuss music without reference to consonan ce/dissonance(C/D), nor that the use of this dimension of harmony is historically and geographically variable, merely that it is a real phenomenon of the Human Ear/Brain system with a fixed range.
   Clearly you can't get more consonant than two notes of the same frequency, but there is also an upper fix point of dissonance within the octave, at its central point, the Augmented Fourth / Diminished Fifth.
The amount of C/D of notes is symmetrical about this point, so if we bend the octave in 2 such that the 1/1 and 2/1 are adjacent you get a diagram which using the first few most C least D intervals looks like this: -

                                                                                              1/1 7/4 9/8 6/5 5/4 4/3
Approx consonance 1to10 10   4    3    6    7    9    0 Middle of
                        2/1 16/7 16/9 5/3 8/5 3/2      Octave

For every interval of a given C in the first half of the Octave up there is a coresponding interval with the same C in the top half down.
Harry Partch wrote a fascinating book "Genesis of a music" exploring this phenomena, and its musical implications.

Here is Partch's more complete and accurate diagram.

All the best PP





All the best PP