private static float[] MakeChebychevLowPass(int filterOrder, double normalizedCutoff, double attenuation) { float[] array = FilterBuilder.MakeChebychevWindow(filterOrder, attenuation); float[] array2 = FilterBuilder.MakeSinc(2.0, normalizedCutoff, array.Length); FilterBuilder.ApplyWindow(array2, array); FilterBuilder.Normalize(array2); return(array2); }