The less expensive and easier alternative would be to ditch the Lumin and get a streamer that has EQ and/or room correction.
Don't hate on me, but I tried very expensive streamers and settled on the Eversolo DMP-A8 and A6 Master Edition for two of my systems. IMO, used as streamers only, bypassing the DACs, they sound every bit as good as the more expensive ones I tried, maybe better in some ways and their app is far better. I would have gone with a Lumin except for their dogma of not going down the path of EQ. While I'm not a fan of DSP for room correct because I think it can make the sound 'thin', I do like the ability to adjust manually with a good EQ.
I personally think this is a better route as it requires less hardware, fewer wires and connections.... FWIW!