why apply filter on the wav and why choose different min max for f0 for different gender

[WilliamZhaoz]

thanks for your great work!

I have 2 questions:

1. in make_spect_f0.py,
   1). why apply a high pass filter
   2). why pad a number if x.shape[0] % 256 ==0
   3). why add some randomness on wav
2. why use different min and max for male and female when you extract f0.

Thanks