miniDSP with separates or Arcam SA30 or NAD C658 plus beefy power amp?

I would recommend a miniDSP SHD Studio which operators entirely in the digital domain and has an excellent selection of inputs and outputs for high-fidelity digital signal transmission.

Then you can take advantage of Dirac or other DSP and routing features while matching it with whatever other gear you want.

We carry miniDSP specifically for the SHD and SHD Studio products to support more complicated setups with Dirac. Learning REW is unnecessary for Dirac, but is still a good skill to have and can be helpful for things like subwoofer integration which 2-channel Dirac can’t entirely address on its own.

miniDSP has a lot of great little "swiss army knife" type products to help fix elements in current systems. However, it’s likely going to degrade some sound quality unless you buy a linear power supply for the miniDSP unit. The switching wal-wart power supplies just aren’t good enough. That being said, it’s much better to buy a really good NAD or Arcam that has the room correction included. That way, you’re not sending the audio through another device that will need to do an analog-to-digital conversion, process, and then a digital-to-analog conversion.

@ataraxia if you have any questions about how you might be able to integrate an SHD unit into your system, feel free to reach out. I've set them up for simple 2-channel Dirac all the way to more complex bass management and channel routing.