During history what it was perceived as consonant for most then became disonant, and the other way around. 6ths were the perfect 5th of their time. Musics of t

During history what it was perceived as consonant for most then became disonant, and the other way around. 6ths were the perfect 5th of their time. Musics of the world uses different afination schemes, and thus different ratios than western musc. As a jazz enthusiast I hear consonance in pieces that most people catalog as noise. (Abert Ayler comes to my mind). My point is that, while there is an underlaying physics explanation for sound and harmony, the ultimate "perception of sound", specially music, is a human trait, where emotion and culture play a much more relevant role than the precision of any ratio between sounds. http://en.wikipedia.org/wiki/Harmony http://en.wikipedia.org/wiki/Harmony (Historial rules, and Perception of Harmony sections are both relevant)