Comment by TylerE

A low-end dedicated DAC is likely to be a substantial upgrade over a built-in soundcard (I'm assuming we're talking PC sound here). A PC case is a pretty noisy place, electrically - I know one one work PC I had once you could actually here the mouse move, if you had heaphones on and cranked the volume with nothing playing - horizontal and vertical movement had different frequencies.

The move from a low end ($150-300) DAC to one much more expensive will be considerably less drastic, and likely won't matter until you've dropped at least $5k in to the rest of your system.

That said, you may already own a DAC without realising it...as long as you're taking the singal out _digitally_ (e.g. SP-DIF or digital coax) to an external receiver, you're already in a pretty decent place.