[wushuliu]

http://audio-gd.com/Pro/dac/USBface/Digital1EN.htm


The USB/SPDIF converter business is booming. There are more options out there than you can shake a stick at ranging from cheapo rinky dink no name models on ebay to kilobuck pedigree. I have only had the opportunity to play at the budget end of the pool, but I and many others have found a winner with the Audio-GD Digital Interface. This is no surprise to some as I've been a vocal fanboy of Audio-GD products for a little while now and slowly but surely their products are starting to get more notice (The Reference DAC 5 was recently reviewed in 6 moons). Until now I have auditioned the stock Hiface, modified Teralink X2, and the Musical Fidelity V-link. Not all at the same time but over a period of 9 months.

The stock Hiface was as many have described, clean but a little too prominent in the upper register and somewhat fatiguing over time (depending on your gear of course). The Teralink X2 has been the mainstay - for $100 the modified version I found to be a much better performer than the stock hiface and cheaper to boot. Add an inexpensive external power supply and you’ve got a real bang for the buck. Leans toward warm sure but retains a transparent presentation. The MF V-link didn’t last long. I was indifferent to it’s performance; neutral, relatively clean but just sort of there. It lacked the depth and body of the X2, and did not seem to have as low a noise floor - the inability to add an external PS doesn’t help in that regard. Plugged the X2 back in and didn’t look back. So that’s twice I’ve tried to jump on the Anything Async is Awesome bandwagon and been disappointed. Seems like you have to shell out a bit more to reap the rewards like the Jkeny Hiface, Halide Bridge, etc.

The trumpeting of async converters has largely been the reason for me ignoring the Audio-GD Digital Interface for as long as I have; burnt by the Hiface and reading feedback on other budget async devices left me wary. The other reason is laziness on my part: their products take a couple weeks to deliver at best, and now that they are starting to get more and more orders the wait time has increased for some products though the DI appears to be ‘in stock’ and ready to ship. I was lucky enough to get mine used at a very decent price. There are two versions, a USB only for $140+shipping and a USB/Coax for $170+ shipping. Shipping to US is roughly $30-35 via DHL,TNT, or EMS. The DI handles up to 24/192 (no 88.2 however), and upsamples at your preferred rate via jumpers. The built quality is better than any of the other three devices I’ve used and the quality components used is ridiculous for the price. It has a Class A power supply. That’s right, *it’s like that*. Wima capacitors, MKP bypass caps. Like all their other products the interior is a thing of beauty. There is no doubt you are getting way, way, WAY more for your money once you take a look. How often does that happen? (note that Kingwa aka Audio-GD won First Prize for National Semiconductor audio design contest in 2007). See the link for all the features and pics.

How does it sound? I am using the DI with no upsampling and 16/44.1 material. Wireworld Ultraviolet USB, Belkin Digital Coax w/ PCOCC copper. So nothing hi-falutin’. From the get-go it was great. As seems typical of Class A supplies there is a definite warm-up period needed. Some say around half hour or more. I let it settle for a couple hours and returned to listen: Much quieter background than any of the preceding converters, separation, imaging, natural presentation, neutral with good depth. It clearly performs at a higher level than the other converters although the modified X2 w/ power supply isn’t too far behind but can’t comepete with low level detail, background, and transparency. Over the next 24 hours the sound improved and stabilized. But it gets better: I used the Jerome Industries power supply popular with Squeezebox modders and the DI benefitted greatly. If there’s a defining characteristic at this time it’s the quietness of the background, which also means you hear so much more low level detail. No digititis present, either.  This transparency is conveyed with ease and flow. For those with top performing digital cables I can’t imagine how good it would sound!

Aside from impatience w/ delivery time and process, there’s no reason to pay the same money for a V-link or Hiface when you can get this level of performance from the Digital Interface.

[srb]

The DI handles up to 24/192 (no 88.2 however), and upsamples at your preferred rate via jumpers.

Reading from the Audio-gd website, it says "The digital interface has USB and coaxial input and both can accept 24Bit/96KHz input.", so although it can upsample to 192, it apparently is limited to 24/96 input.
 
For my application, I was excited to find and hoping to be able to use both the RCA and BNC coaxial outputs simultaneously, but the very next sentence answered the question I was about to pose to you, "It has RCA and BNC output but users can only use one at a time."
 
Steve

[pardales]

Nice review, thanks. 

I set-up my computer based music server back in 2005 and for the first few years tried nearly every converter made -- there were only a handful in the first few years -- I think the Waveterminal U24 was among the first, and was the first one I tried. I've kept trying them on and off over the years including some more expensive ones from Empirical Audio and bel Canto.

Finally, when USB DAC's started to appear I was glad to be able to do away with the extra conversion step and extra cable. I have learned that not all USB implementations are created equal, of course, and there still can be a place for converters such as this, especailly if you don't use a USB DAC or don't have a quality USB implementation on your DAC.

[wushuliu]

Reading from the Audio-gd website, it says "The digital interface has USB and coaxial input and both can accept 24Bit/96KHz input.", so although it can upsample to 192, it apparently is limited to 24/96 input.
 
For my application, I was excited to find and hoping to be able to use both the RCA and BNC coaxial outputs simultaneously, but the very next sentence answered the question I was about to pose to you, "It has RCA and BNC output but users can only use one at a time."
 
Steve

Yes, thanks for clarifying. Didn't mean to get your hopes up!

[Alexdad54]

I'm using the Audio-GD DI as well with its companion PSU and am really enjoying it. I was wondering if you replaced the Audio-GD PSU with the Jerome Industries power supply or did you not buy it originally?

[srb]

Yes, thanks for clarifying. Didn't mean to get your hopes up!

That doesn't mean that within the 24/96 input capability, that it isn't a good or great converter, and maybe better sounding than some others that have higher-res input capability, as it seems you have found.
 
Because my music server and video server coexist on the same PC, I have avoided USB interfaces, as I need to send one output to an AVR to decode Dolby Digital for TV/Movies and another to a 2 channel DAC for Music.
 
I currently accomplish this with simultaneous coaxial and optical S/PDIF from an integrated motherboard Realtek chip.  When I saw the dual S/PDIF outputs on the Audio-gd, I was hoping maybe I could do the same with this USB interface.
 
Steve

[JohnR]

What's a "Class A power supply"?

[wushuliu]

What's a "Class A power supply"?

You know that's a good question. I just assumed that he uses shunt regulated power supply or similar.