Yes, Quad CDP or CDP-2 have both coax and toslink inputs so you can connect an external digital source.
Not as affordable, but the resolution Audio Opus 21 has a coax input for connecting an external source.
A nice feature of both the Quad and the Opus 21 is that they have built-in remoted controlled variable volume control. So, if all of your sources are digital and are going through the CD player, you don't need a pre-amp. You can connect the CD player directly to a power amp and control the system's volume through the CD player.
Enjoy,
TIC
