I use a usb conveter too from my pc to the coax input of my K-01 player. Once you have gone this route, you can never go back to usb direct. The coax input makes everything sound whole and right.
Esoteric K-01 and Mac music server
I am considering the Esoteric K-01 as my digital source and also want to know that it works well with a Apple Mac as High Res music server. Does anyone have experience with this unit or the K-03 with a mac?