New DAC or player?


After a lot of upgrading I now think it's time to work at my (digital) source, a Marantz 63 KI. Already owning a Musical Fidelity X-Pre and X-PSU, I'm tempted by the X-DAC that appears every now and then secondhand for very reasonable prices. But would it be worth buying one? Would another DAC be better? Or is the Marantz, tweaked as it is, not really a good transport and would a new (other) player be a better idea?
Any input is appreciated.
satch
I went through the same exercise a few years ago w/ a 67SE.
I tried all the reasonably priced DACs Du jour(MSB,PS audio and the Bel Canto 1.0 ) I ended up w/ a used CAL Audio Alpha
and found the combo to be one of the most analog sounding setups I've ever heard. The Alpha is truly old technology
( 18 bit bitdac) but a winner when loaded w/ good NOS tubes
and resonably cheap here on Agon.
Thanx guys, opinion seems to be a bit divided between a DAC and a new player. I don't know what I'm gonna do yet, I'll just check out the secondhand market and see what'll come my way. And Poetcallus, I wouldn't mind owning the Sony, I always liked their ES-line, but since I live in Europe and I got the feeling you don't, that is a bit of a problem. I did see a nice Meridian player on some other board, but also a nice (Dutch) Van Medevoort DAC, so.....
The Sony ES line is one of the best imo. I'm using an Dvpnc 555ES with the digital filter set to slow. It sounds excellent through my VMPS RM 40's which are extremely transparent. The warranty is very good too.