External clock to network switch

The After Dark 10mHz clock cannot be connected to Bartok, which as Ludovic notes only has word clock inputs. But your After Dark clock could be used as a reference clock for any word clock you did supply to Bartok. However, its design is not likely to contribute significantly to improving the performance of the dCS clocks for reasons that have been articulated in other threads here. I also concur with Ben. Although one can connect a reference clock to upstream switches like an EtherREGEN (and I have done so in my system just for the fun of it), it appears to have zero audible effect on SQ, and there is no sound reason to think it should (as also discussed elsewhere in this community).