Octave harmony in instruments and singing are established physical phenomenon. Higher harmonics of two voices line up and resulting frequency spectrum is more c

Octave harmony in instruments and singing are established physical phenomenon. Higher harmonics of two voices line up and resulting frequency spectrum is more clustered and concentrated. I think the study disproves that all brains consider this to be preferable, and instead ascribes it to cultural/learned phenomenon. I agree it's not compelling theory, but hard to argue against if they can get more proof.