I have no idea what most of it means :)

DAC technology evolves over time; some companies prefer certain methodologies (1-bit - bitstream, was very popular when I bought my home CD player in around 1990, and Philips like it). "Noise shaping" was something which used to appear on a lot of panasonic gear, but I have no idea what it means. Oversampling just means outputting the DAC value multiple times to average across multiple sets (though how this would make a difference at the sample/hold stage in such a short time period, I don't know).

Generally, PC cards sound bad simply because they have cheap DACs, cheap DAC PSUs (not generally independent ones from the "dirty" digital PSU), cheap PCBs (not multilayer usually), cheap audio path components and cheap connectors. You get the same effect with very cheap consumer CD players (like the ones which cost $60). When you get to $150+, you're no longer just paying for a decent CD mechanism that doesn't skip for a pastime and you start paying to improve the PSU, improve the DACs, get some decent capacitors in there - that sort of thing.

The empeg has independent linear PSUs to drive the audio section, a good multilayer PCB, and good components: we didn't cut any corners. That's not to say we couldn't have made a more expensive audio output section (by putting offchip DACs in there) but we believe the output is about as good as it gets from the DACs we use. In short, the empeg audio section was designed as a consumer audio part, not as an afterthought on a computer - as most laptop audio circuitry is.

Hugo