In WinISD Pro Alpha there is a filter called "Peaking 2nd order highpass". I'm working on a design that uses the "ESB3 extended bass shelf -3dB" option for the box. When properly set, the peaking 2nd order highpass nearly perfectly corrects the -3dB shelf and cuts off any extremes at the low end of the spectrum. However, I can't find any information about what exactly is going on with that filter or how to implement it. So...
-- What is the "Peaking 2nd order highpass" and how do I implement it in DSP?
-- What is the "Peaking 2nd order highpass" and how do I implement it in DSP?