For SPDif the Rega DAC-r using filter 3 and fed via a Belden 4794R cable (with a BNC to RCA adapter at the DAC end) this combo let the emotion flood out. When first tried using a Chord Shawline it failed to excite but with the Belden (~$20 from blue jeans cable) it came to life. I fed it from a Naim Core, I never tried USB its USB imput.