Please 'splain. I don't find a definition of word "voice" that pairs up with a definition or application of the word "reason," here.
Of course I can tend to misplace things.
"Voice" really doesn't line up with "reason" in the sense I gather you suggest here. What "Voice" is, is B. speaking his musical conception via the mechanical construct of the physical horn, interpreted by the listener to whom he appeals as a meaningful experience of some kind.