If you use headphones only just go with STX, keep in mind that PCI on mb's will be gone sometime down the road. I have STX and i love the card but Asus has the worst support in the world and seeing that the Win7 drivers are still in beta i wonder if they even support this card anymore? On the other hand Omaga has excellent support and will even answer your emails within hours.
STX has 180ps jitter, in other words, inaudible.
The ST measures worse according to several posts I've seen, so imo the jitter is irrelevant. Haven't found jitter measurements of ST.
I'd get the STX myself, unless:
a. you need to use a pci slot
b. you need the addon card for more channels
But sadly nedaroth is correct, you'll get no support from ASUS driver wise. They make big promises and a halfarsed reply on the support forums then vanish and 6 months later you'll see a new release of broken drivers.
IMO it's not a terribly big issue at this point unless you're desperate for WASAPI/ASIO, but when Windows 8 rolls in you'll probably be waiting a year or two on drivers.
Rubbish, and when i got to the mac and itune part of the review i quit reading. in the end he could not recommend eather one. Hell give asus and omaga credit for bringing something to the table, Stereo Review years ago was credable, i want a review on a card intended for a PC i could care less about mac and itunes.
But back to the case at hand i dout you would notice enough sound difference between the two to sway you one way or another, Get the one that better suites your needs.
Cut it out. I just got Win7 x64 a few months ago and I'd like to be able to enjoy it for a bit.
I agree on ASUS tech support. Those guys are about as clueless as clueless can be. But one point, ASUS does have a full Win7 x64 driver (version 17,12.8.1777) but you also have to download and install WinRAR to be able to use it. Once you do that, it installs right in and all's good.
"Fig.15 ASUS Xonar Essence STX, line input, spectrum of 44kHz sinewave at –12dBFS, 24-bit data, 192kHz sample rate (left channel blue, right red; linear frequency scale).
The ST (PCI) version of the Essence didn't measure quite as well as the STX (PCI Express) version, but both still offer very impressive sets of measurements for a product that is a) affordably priced and b) must be housed in the hostile RF environment of a personal "
"Word-clock jitter in the STX's TosLink S/PDIF output, measured directly with the AP SYS2722 and a 44.1kHz datastream, was low at 1.48 nanoseconds, which is close to the system's resolution limit. Jitter in the analog output, assessed with the Miller Audio Research analyzer, was very low at 170 picoseconds left and 186ps right."
So they measured the ST and STX, ST measured worse. Looks like they didn't measure the jitter (which comes from clock circuit) of the ST - but the jitter level of the STX was well below the audible threshold. So it doesn't matter if the ST has less jitter or not.
ST is only better if you NEED to use pci or are going beyond a 2.0/2.1 setup.