I currently have a Big Ben master clock routing to my RME FF800.

My FX Processors dont have a dedicated WC input, so I assume I need to run my S/PDIF to my soundcard. However, is it critical that the soundcard would be a slave clock (from the Big Ben) or does it have to be a master?

Can I route the Big Ben to the FX processors directly via an optical channel just for clock purposes?

I should know this...