Finally, finished my flanking subs. I am using 2, 15" Drivers from Parts Express in ported enclosures.
For flanking subs, you said "just set it for low-pass 100Hz BW 12dB/Oct." For this I am going to use a miniDSP that I have from a previous project (LXmini from Siegfried Linkwitz). It will be super easy to set the recommended low pass filter in the DSP. Should I set a high pass filter as well?