Schiit Yggdrasil or Simaudio Supernova

I presently have a Supernova, but am considering a Yggy, keeping the Supernova as a transport.  Is the Supernova BurrBrown PCM1798 chip a Delta-Sigma or multibit design? What would be the sonic differences between the Yggy and Supernova? The Supernova is a really nice sounding machine, maybe a bit clinical.