PC S/P-DIF quality

[goldsdad]

Good evening.

 

My first post here as I'm about to embark on the computer-based audio path, and this forum definitely looks like the best place for guidance.

 

My now unreliable computer is about to be replaced by a general purpose home PC running MS Vista 64, primarily but not exclusively for use as a low-cost music server outputting to a DAC.

Music will be lossless ripped CDs and downloads at various sample rates up to at least 24/96.

 

1. Any advice regarding the quality of S/P-DIF (coax and/or optical) output of current ASUS motherboards? These mobos feature various onboard 24/192 HD audio, for example:

ADI AD2000B

Realtek ALC883

Realtek ALC1200

VIA VT1708S.

 

2. Would there be an improvement from using a low-budget (max £100) gaming sound card or home studio card like ESI Juli@ or MAYA44 for S/P-DIF output, bearing in mind that the card would be used solely for pass-through of digital audio? If so, please recommend particularly good cards if possible.

 

3. The equipment will be in one room, but it's impractical to have the PC close to the hifi. Are problems to be expected from using a 10m length of coax or optical cable between PC and DAC?

 

4. Are there generally agreed advantages of coax over optical, or vice-versa? Or is it a case of "it depends..."?

 

Any other info, suggestions or recommendations to a noob are most welcome.

 

Thanks and best regards.

 

 

 

[davidR]

Hey goldsdad welcome to the boards. It's great to have you here.

 

1. The SPDIF / Optical outs of motherboards aren't great sources. They aren't terrible but output noisey, jittery signals compared to other options out there.

 

2. Yes, a home studio card like the ESI Julia@ is a great option for pass through and would offer better sound than onboard.

 

3. If you are talking 10 meters SPDIF would be the way to go over Toslink.

 

4. It can be a controversial topic like many in audio where sounds are so subjective and everyone has a different set of ears and brain but SPDIF is stated to be better for longer cable runs because toslink has signal loss at a certain length much shorter than that of SPDIF. Also the amount of jitter (timing inaccuracies of 0's & 1's used read by the DAC) of Toslink cables is said to be greater than that of digital coaxial cables in general. Toslink cables aren't prone to EMI noise like SPDIF but unless you are getting an audible hum with the SPDIF connection there isn't an issue.

 

[goldsdad]

David, thanks very much for the reply.

If only one could go to shops and listen to alternative gear before purchase, like with traditional audio, eh?

I need to give more thought to this situation then, no doubt, I'll be back with more questions.

 

 

 

 

[robjob]

I'm retasking my desktop to media and just swapped out my SoundBlaster with an ASUS Xonar D2/PM. This card is the only sound card I could find that would pass 24/192 through the SP/DIF coaxial output. I've had it installed for about 2 weeks and so far I'm impressed. Mobo based sound just can't live up to the quality of a peripheral PCI/PCI-E sound card. My current rig includes the PC(W/ASUS Mobo), the xonar connected via 25' coaxial cable to an MSB DAC, NAD Preamp and Amp with Mirage 490 speakers.

 

[WoodsDweller]

I was wondering when somebody around here would try one out. There are a bunch of models:

 

ASUS site

 

How did you settle on the D2/PM? I guess only that one and the Essence STX are showing 24/192. I was toying with the idea of an Essence STX.

 

First I'm going to test the motherboard S/PDIF to have a baseline for comparison. The bracket I need should come in next week.

 

 

 

[The Computer Audiophile]

Excellent plan WoodsDweller. I'm very interested to hear about results after using the built-in S/PDIF as a baseline.

 

[WoodsDweller]

The bracket experiment is going to happen, since it is on order. A massive $44 including tax, shipping, and a cable. The first thing will be to see if it is an improvement over USB (which I am inclined to think it may be). I have the 24/96 sample album from HDtracks and its 16/44.1 counterpart to serve as a test case.

 

Beyond that, we'll have to see. The Xonar cards are in a nice price range, and my DAC/amp has no AES input, so S/PDIF is what I've got to work with.