Look at the soundcards made for studio recording professionals, like the above-mentioned RME. They often have word clock ability. But even within this group one must be careful since judging by specs alone is worthless. I run a pro recording studio, and can tell you that two different pro audio cards, similarly priced with the same specs can sound completely different. One can be sweet, open, and three dimensional, while another with the same specs can be rather brittle and closed sounding. It mostly has to do with the quality of the converters. RME is an amazing choice, as are products made by Lynx, and Apogee. I would not recommend Mark of the Unicorn, and Emu has a great bang-for-the-buck card - the 1820M - that rivals the 1st three mentioned.
Soundcards with wordclock input
I've read that if you use a common wordclock between transport and DAC, then you can reduce (eliminate?) jitter. I've seen only one card that has a wordclock input made by Marian. Are there others or others that are better?
Also, is it better to use 1) a soundcard with a wordclock input or 2) a USB device (e.g., Waveterminal)? It seens that you would need a wordclock input in the Waveterminal to eliminate jitter between the Waveterminal and a DAC.
Also, is it better to use 1) a soundcard with a wordclock input or 2) a USB device (e.g., Waveterminal)? It seens that you would need a wordclock input in the Waveterminal to eliminate jitter between the Waveterminal and a DAC.