Dear Rolf, dear All several years ago I had the same idea and solved it by using a modified Butterworth design (analog) and a Frequency Domain Least Squares (FDLS) Design for the final digital filter. (Never published it.)
I just finished my first blog-post about it. (This question was a good motivation to finally start my blog and to start with Python. Thank you for that.). https://dspblog.audio-dsp.de/ A Jupyter Notebook to play around with the method in Python is provided. BTW: It also solves the problem of the bilinear transformation distortions near Nyquist. You pay with computational complexity. Best regards Joerg Am 29/06/2018 um 18:06 schrieb rolfsassin...@web.de: > Hello Robert > thanks, so this means that it will come out with a cascade anyway. Would'nt > it > then be generally better to put filters in series or use parallel band width > limited filters though? > Regards Rolf > *Gesendet:* Mittwoch, 27. Juni 2018 um 16:49 Uhr > *Von:* "robert bristow-johnson" <r...@audioimagination.com> > *An:* music-dsp@music.columbia.edu > *Betreff:* Re: [music-dsp] EQ-building with fine adjustable steepness > So with a one-pole LPF with its corner frequency set very low, you wI'll get > a > -6 sB slope, which is twice the slope that you desire for pink noise.if you > follow that with a zero, the slope will bend back to zero slope. > So repeating and alternating poles and zeros, will get you a slope somewhere > between 0 and -6 dB per octave. If you start with a pole on the left and > follow > it shortly with a zero, it will be closer to zero. If you have more space > between the pole and zero frequency, then the slope is higher. > > > > _______________________________________________ > dupswapdrop: music-dsp mailing list > music-dsp@music.columbia.edu > https://lists.columbia.edu/mailman/listinfo/music-dsp > _______________________________________________ dupswapdrop: music-dsp mailing list music-dsp@music.columbia.edu https://lists.columbia.edu/mailman/listinfo/music-dsp
