First impressions, as compared to Essence ST (both with HD555s w/ soundstage mod):
The control panel is a stripped version of the regular Xonar, as the card itself is lacking a lot of technologies. No Dolby Digital Live encoding, max sample rate 96 KHz, lower headphone amplifier gain settings (below 32 ohm, 32-64, and 64+ (to max 150 ohm if I recall)). The card does have GX2.5 EAX emulation for positioning and Dolby Headphone. Also has 5.1 analog outputs, which the Essence does not.
The sound is somewhat lacking when compared to the Essence, without me being able to pinpoint it. More sibiliance? Less precise bass? Less natural mids? Definitely more listening fatigue. I am afraid I lack the precise vocabulary and experience to describe it better. The sound is good, (compared to onboard) but unlike the Essence this card does not make me smile.
In sum, the DG is head and shoulders better than the onboard sound it is replacing. At 1/5 of the cost of an Essence, I would definitely recommend it for any budget gaming rig. It does not encourage me to spend hours listening to music, though.
Edited by kevral - 11/5/10 at 10:29am