Ted -
Those are some very simple questions with complicated answers. I think some background might be in order...
So I am curious to know if you would be willing to share how the Auralic compares to the AVA DACs?
First off, let me say that, in my opinion, the AVA DAC is a wonderful piece of equipment. It was my go-to DAC for a couple of years when used as an outboard DAC with a standard CD transport and I still use it today. But when I went to audio shows, CD's simply became impractical and I started to look for a streaming device that would serve my needs.
My first attempt at assembling a workable system was a Sqeezebox linked to a dedicated Linux computer feeding the AVA DAC via S/PDIF. But it was far from ideal. I didn't like having to lug a computer to shows. Although the Sqeezebox worked, it wasn't exactly an elegant solution. And it required server software that was prone to occasional crashes (not desirable in the middle of an audio show). What's more, as higher resolution files became available, it was limited to 24/96.
While many people feel anything over 24/96 is overkill, I thought as long as I was looking for a solution, I may as well look for one that could handle all the various resolutions that were obviously on their way.
Nick Lidakis read about my desire to move to something that could handle higher resolutions files and we exchanged many emails and phone calls on the topic. Out of those conversations, the StreamPlayer was born.
But now I had an issue. At that point in time, I could stream 24/192, but the AVA DAC (as I recall) had no USB input. Converting from USB to S/PDIF kind of defeated the purpose. Frank and I talked about it quite a bit, but he was very hesitant to add USB support (at the time). I certainly couldn't blame him. At that time, it seemed like every type of computer operating system required a different driver and the support required would be very difficult for a smaller company like AVA. Frank is an extremely competent and talented analog guy. But supporting drivers for computer operating systems is simply not in his repertoire.
I should point out here that there are a lot of DACs on the market that can support 24/96 playback without issues. But when you move up from there, it gets complicated. At those higher resolutions, all DACs require special drivers with Windows systems and many require special drivers for MAC's as well. For DACs that require special drivers for MAC systems, Linux support is almost non-existent. The Windows OS can't handle anything over 24/96 without special drivers. So that is a given no matter what DAC you use. But if the USB input is USB Class 2.0 Audio compliant, you don't need special drivers with the MAC or Linux operating systems. And given a choice between a DAC that required a special driver and one that did not, I know which one I would choose every time (I view any device requiring a special driver with extreme caution. If you ever upgrade your operating system, you better hope there is driver support for it.) With our StreamPlayer, for example, if the DAC is truly USB Class 2.0 Audio compliant and is capable of 24/192 resolutions or above, it is truly plug and play.
Since Frank wasn't all that interested, I did a search and found a USB Class 2.0 Audio compliant input board that seemed to work (XMOS). Frank was kind enough to install one in my AVA DAC so I could use it with the StreamPlayer. He also found one from miniStreamer that could at least do 24/96 without the need for special drivers.
About that same time (before we had tested the XMOS or miniStreamer options), I needed a 24/192 DAC to test our StreamPlayer. So I talked to Gordon Rankin who had gained a reputation for producing high quality DACs with excellent USB support. He built one of his Wavelength Cosecant models for me. I could be wrong about this, but I think it uses a Wolfson chip-set as well. So the sound quality was similar to the AVA DAC (of course the Cosecant is twice as expensive).
In terms of PCM playback up to 24/192, the Wavelength DAC has performed flawlessly for as long as I've owned it. While working with the XMOS or MiniStreamer USB inputs was slightly challenging at times, the Wavelength DAC has NEVER skipped a beat. As far as high resolution DACs are concerned, it performs absolutely flawlessly at any resolution up to 24/192. I have never experienced a pop, click, dropout or any other anomaly - something I can't say of most DACs we have tested. It just works.
Not too long ago, I was approached by the US Distributor for Auralic about the potential use of our StreamPlayer with the Auralic Vega DSD DAC. Of course I was quite interested in this project. But now we move from the leading edge to the bleeding edge.
Most USB-based DSD DACs use DSD over PCM (DoP). The DoP v1.1 protocol allows native DSD playback without conversion to PCM. The DSD files are configured as PCM packets, transferred via USB to the DAC and unpacked for native DSD playback.
But the DoP v1.1 standard is relatively new and implementations vary widely. Many of these DACs require special drivers (again, I have a built-in bias against anything that requires a special driver). For example, the exaSound has earned a great reputation for their DSD DACs. But they require special drivers and don't support Linux at this point in time.
With a little tweaking, I was able to get the StreamPlayer to stream DSD64 and DSD128 files using DoP. The Auralic USB input did not require any special drivers to handle PCM or DoP. Once I got the units communicating, other than a few issues from time to time, the StreamPlayer and the Vega played fairly nicely with one another.
As for the sound, about the easiest way to describe it is to say that it is a little less warm than the AVA or Wavelength DACs. This is not bad, mind you, just different. It is a very clean, clear and detailed presentation that is hard to find fault with. But given a choice, I imagine some people may prefer the slightly warmer sound of a DAC based on a Wolfson chip set. Others would prefer the clarity of the Vega.
One nice thing about the Vega is that it is a preamp with multiple inputs as well. I have used it to directly feed my amp, eliminating the need for a separate preamp. While you could certainly argue that a great preamp would improve sound quality, the simplicity of this set-up does have some appeal.
Is the Vega the perfect DAC? It is certainly an impressive piece of engineering but, at this point, I can't say it is perfect. DSD over PCM via USB is relatively new and there are a few hiccups at this point. I expect all of these will get ironed out in the near future, but expect a few bumps in the road if moving to DSD playback at this point. Specifically, I have experienced a loud "pop" from time to time when switching from one format to another. Sometimes the Vega loses sync and even though it is being fed a stream and correctly identifies the resolution, there is no sound. A Vega re-boot solves the problem. And when starting from scratch at a new resolution, at times you will miss the first few notes of a song (I assume it takes a little time to identify the resolution of the stream being played). In comparison, I've never experienced any of these issues with the Wavelength DAC (or the AVA DAC at lower resolutions). I should note here that I have experienced issues like this with many other DACs. Perhaps these hiccups are just the price you pay for being an early adopter.
I should also point out that these are fairly minor irritations. I have used the Vega DAC for days on end at the shop and for the entire week-end at CAS. At CAS, I think I had to reboot the Vega once in three days and once and a while listeners were surprised by a loud "pop" between tracks. Other than that, it performed well.
At this point, I don't know if those issues are due to the Vega or due to the maturity of the technology. We just got another DSD DAC in this week and I hope to have time over the long week-end to test it out. We'll see if the above anomalies show themselves with this DSD DAC as well.
In terms of future development, I have no idea what Frank has in mind for his DAC. But my advice to him would be to hold back on DSD development for the time being. There is not a lot of DSD material available for those who are not keen on ripping SACD's. And the technology needs to settle down a little before the demand for DSD playback becomes more mainstream. So there is no need for Frank to rush into at this point and some very good reasons he should not.
Speakers fortunately handle all formats don't they?!
They certainly do!

Also can you explain how the SalkStream handles DSD files? Is there any special preparation that needs to be done to the files?
I explained DoP above. It allows the DSD file to be packaged in a PCM framework, delivered via USB and decoded at the DAC into the original DSD file for native DSD playback. The StreamPlayer can handle both DSD64 and DSD128 files in both .dff and .dsf formats. Nothing special needs to be done with them.
Sorry for rambling, but I thought a little background detail might be helpful. I hope this answers your questions.
- Jim