Its nonsensical to believe dacs act as a noise conditioner for detail obscuring noise further upward in streaming chain. The only sense of 'conditioning' a dac can possibly achieve is optimizing certain inputs, this usually usb on most dacs. Galvanic isolation is one of the ways they achieve this, dac manufacturers understand they are only one link in streaming chain, so attempt to optimize how they interface with rest of chain. Interfaces amongst all the other components within a streaming chain require the same optimization dac manufacturers provide, data is traveling across the entire chain. And interfaces are only one consideration, minimizing noise within components is fundamental/a priori to achieve lowest noise floors for max resolution/transparency. And we haven't even gotten to clocks within these components, this has everything to do with presentation. And so are we going to argue that clocks makes no difference.