I'm just guessing here. What stands out is that the extrema of that octave have the same value. I would guess that this means that things are probably especiall

I'm just guessing here. What stands out is that the extrema of that octave have the same value. I would guess that this means that things are probably especially well-behaved in that region. If you look at the Chebyshev series of log in that range, you may see some very small coefficients.