You would need a surround processor to replace the G68. Then you would need a 271 plus a Reviver/AC12 for every pair of DSP speakers that you plan to use.

There have been serious issues with many new Atmos processors this year (Arcam included) Lyngdorf seems to have been immune to this but availability has been an issue.
Newer processors also allow you to skip the HS621 or UHD722. I think the Lyngdorf MP60 is the most affordable processor offering digital outputs.

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