Explain to me dsd

Ok so I understand dsd was a way for sacd to be computer storage friendly...

But I have a dac (Emm Labs Dac2x) that somehow uses dsd (I'm confused as to whether it up samples to dsd)...

Can someone explain to me what this is about and whether I would benefit from a streamer like auralic Aries that is able to output dsd vs a bluesound node 2 that outputs only pcm?