Active line level crossover with subwoofer out - HELP

My (limited) understanding of room nodes is that they are affected by the placement of the subwoofer (or subwoofers, as in a swarm).  If that is true, can a single mini-DSP fix the room nodes regardless of subwoofer location?  Or do you need one mini-DSP for each sub?

@heaudio123   Thanks for the info.@erik_squires -- If I remember right, you are a proponent of standalone DACs (specifically Brooklyn), DIY swarms, and dedicated multichannel subwoofer amps, in addition to miniDSPs. Assuming that's so, do you put the miniDSP between your sources' digital output and the dedicated sub amp? If so, I assume you use a second digital out from your source to feed the Brooklyn DAC; do you also use a filter after the DAC to dampen the bass below a given cutoff frequency for your main speakers? Finally, do you use a different output from the miniDSP to each of the subs, and tune each one differently? Sorry for so many questions...