Assuming the center would be DSP as well, the 218 speakerlink output would need to be connected to that speaker. Comms is another story. I don’t have a way to mock this up to try it but you really cannot damage anything connecting speakerlink inputs to outputs. You would need to set whichever device you want to be controller and the others not controller. Connecting BNC comms out of the slave speaker to the center comms in just might do this. Set the 218 to use the analog input to whatever source key on the 818 you are using when connected to the SSP.

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#1 Trinnov Altitude 32-8-16, 271, 8000XE, 7200SEHC, 7200.2, Seaton F18, JL Fathom F113, Revel w990's, Kef R7, ATI 528 Amp, JVC RS4100K, SI screen. Roon Nucleus+, Eno AG, Eno M link, 218.
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