BACKGROUND: All my digital music files are in uncompressed WAV format. I control these through Media Monkey software, which I currently listen to through only my computer speakers. My question is about how best to get high-quality sound (at least 24-bit, 96-kHz; hopefully even 24-bit, 192-kHz) from one's computer to a high-quality A/V receiver, which is located in another room.
SOUND SYSTEM: My main sound system (in a different room than the computer) consists of a Marantz 6003 A/V receiver and, for music, a 2.1 speaker system (L&R monitors a subwoofer), and two surrounds for movies only. Connected to the Multichannel analog inputs on the receiver is an Oppo-83SE CD/Blu-ray player. The receiver has analog, HDMI and S/PIDF Toshlink optical inputs.
COMPUTER: I built my computer using an Intel DH67BL motherboard, which has a Realtek ALC892 audio codec and outputs through (1) standard minijack speaker outs, (2) S/PIDF Toshlink optical output, and/or (3) HDMI out.
ISSUE: As I began to consider running the music files through my A/V receiver, I researched the idea of purchasing an audiophile-grade (not for games, just music) computer sound card (24-bit, 192k-Hz capable) having RCA-jack audio outputs. Apparently ASUS makes an excellent such product, the Xonar Essence STX; I'm sure there are others. And then it occurred to me that all such sound cards incorporate D/A conversion circuitry to convert the digital signal to analog, thereby feeding an analog signal to the outboard preamp or receiver. I my case, however, since my computer motherboard incorporates an S/PIDF Toshlink optical output, why not nix the purchase of a separate sound card and instead run a Toshlink optical cable from the computer to the Toshlink optical cable input on the receiver? Or, perhaps, I could instead run an HDMI cable between my computer and the A/V receiver, but my intent is for high-quality audio, not video.
Of course, in using a Toshlink optical or HDMI connection I would then be using the receiver's D/A converter circuitry rather than that on a sound card, but I suspect that the D/A converter circuitry in my $1300 receiver should be at least a good as that in the $200 ASUS (or other) sound card.
Is there any opinion on these (or other) alternative methods of bringing high-quality sound to my Marantz 6003 A/V receiver from the computer?