Kind Regards

]]>the problem that the Massberg desgin tackles is that simple digital LP-filters go down to -oo at nyquist but analog filters do not. So the EQ-Curve is quite different at the very high frequencies: Analog filters more or less hold their slope up to "infinity Hz", e.g. attenuating 12dB each octave a second order LP at 20 Hz would reach about -120dB at 20kHz while the digital filters "stop" at nyquist and map nyquist to infinite attenuation. The Massberg design thus generates a more high-shelving-filter-like curve at the top end, corresponding closer to the analog curves.

On the other side of the spectrum, 0Hz "analog" can be easily mapped to 0Hz "digital", so the problem that the Massberg design covers does not exist to that extend in the low end.

Regards

Tom

Firstly, a huge thanks to Will for giving me a huge step up into DSP, the book is amazing and rackAFX is absolutely incredible for beginners!

Whilst I am learning so much each time I re read the book, I haven't quite got to the stage where I can see how the formula's were derived and was wondering is there a HPF equivalent to the 2nd Order Massberg filter shown late in chapter 6?

I cant find much on the internet about the filter so I thought I would ask here!

Kind regards!

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