Hi. I'm in the midsts of building a new HTPC and one item that's struck me is that my motherboard, the MSI Z87I, comes with Realtek's ALC892 on board. I was planning on outputting my audio into a Marantz NR1603 via either HDMI or Optical. I was hoping to try Optical so I could at with higher end audio EQ software or a separate USB sound card altogether.
That being said, I have some basic Windows related sound processing and output questions I haven't been able to answer.
First, when outputting audio from Windows 7/8 via HDMI using a video card, the video card drivers have to include a HDMI driver to support this. Is there any audio quality difference (less interference, EQ bypassing, etc not just on paper SNR numbers) or advantage to using HDMI audio over Optical? Besides the convenience of a single cable?
Second, considering that Optical would be used, would there be a benefit to using a USB sound care like the Creative X-Fi? I realize part of this difference would be software, but I'm more interested in knowing if a higher quality sound card would offer a benefit over on board audio when outputting over Optical.
If we were talking headphones or general analog output (5.1 audio analog plugs) the answer would always be the separate sound card, but with digital outputs it's not as clear to me. My initial expectation is that it's a waste of time and to just use the HDMI audio output, but I have quite a good HT setup now and would like this build to do better than my old HTPC if possible. (It was fine but I'm trying to see if there's a better option)