I would be surprised if the quality of the SpeakerLink on the 218 is equivalent to the SpeakerLink output of the 861.

Wiring as suggested (861SL -> 218 -> DSP8000) will likely bring the output performance of the 861 down to that of the 218.

For audio, consider investigating instead wiring the 218 in parallel with the 861 using D2 on the DSP8000's. Not sure how comms would work though - you may need to keep that in series or put 218 indo D1(SL) and 861 into D2 + comms - latter may be treated as a second room system as far as D8k's are concerned. Or comms may not matter although IIRC that MQA capability handshake occurs over comms.



Meridian owner since 1992
Prime & PSU, Focal Elear headphones, Roon (ROCK 8Gi5 NUC), Explorer 1 & 2, F80. 200/203, various Sonos (via Roon).