Theta are only just getting started with Dirac Live. There are a number of areas in my opinion where the functionality can be improved and the team are feverishly working on the software of the CB IV (hopefully picking up on some of the things I would like to see). Even if you decide, for some peculiar reason, you want to constrain Dirac to a particular frequency range such as below the Schroeder frequency of your room (assuming you are even able to calculate it accurately) the base management that is available from a system like Dirac dwarfs picking simple cross over settings in the controller. And that's before you even start thinking about what additional cream a Gen VIII S3 can deliver.
Egglestonworks Andra III, Andra III Centre, Rosa (as surround). Rel Stentor II. Theta CB IV. Krell FPB 200 and two KAV 150a amps. Custom-built audio server. Oppo 103EU. Apple TV. Pioneer PDP-LX608D. Synergistic Research "Element Copper" front speaker cable. Cardas Clear Light bal interconnects.