Hi, in the documentation is a new example for afftfilt: afftfilt="real='hypot(re,im)*sin(0)':imag='hypot(re,im)*cos(0)':win_size=512:overlap=0.75" What's the point of multiplying by sin(0) and cos(0)? Isn't this exactly the same as afftfilt="real=0:imag='hypot(re,im)':win_size=512" Michael