Mm622 hi, do you listen to mainly Redbook cd's?
The reason I ask is that Redbook is PCM and to get "Bit Perfect" conversion the best way, is for it to converted using a Ladder Multibit dacs, which your Esoteric X-03 has, and the best ones at that the PCM1704's, which have been phased out recently because they are more than 10 x the price to manufacture than Delta Sigma dacs, and never to be seen again, only in discrete form with companies like MSB do with their $40K Diamond DAC V.
"ESOTERIC X-03 4 x PCM1704 – SM5847AF VRDS-NEO VMK-3.5-10 – SPU3162"
Sending a Redbook PCM digital signal to a Delta Sigma type dac ( which are in the Esoteric K-03X vs Accuphase DP-720 so they can do DSD and SACD) is taking a step backwards from what you already have for Redbook cd replay.
So saying this if you play mainly Redbook and have no interest in DSD or SACD. Stick with what you've got, which is one hell of a machine for Redbook CD replay.
I would kill to have your Esoteric X-03SE
Cheers George