It's because eleven notes is the maximum that fit "nicely" into the harmonic series our eardrums pick up: http://en.wikipedia.org/wiki/Harmonic_series_(music) h

It's because eleven notes is the maximum that fit "nicely" into the harmonic series our eardrums pick up: http://en.wikipedia.org/wiki/Harmonic_series_(music) http://en.wikipedia.org/wiki/Harmonic_series_(music)