Does this dac exist?

What I am looking for is a dac that accepts I2S from the computer without the need for an additional converter.

There is no such thing. In order to get I2S, you need audio controller. Whether built-in, USB or Firewire, there must be one.

Why I2S? You think it sounds best?

Best,
Alex Peychev

Here is what the Wyred DAC-2 manual says about its I2S input:

The W4S DAC-2 is equipped with a balanced I2S connection via HDMI. Please note that the DAC will NOT offer playback from typical HDMI output connectors found on many DVD players (or similar devices), and damage can occur if connected to such. The HDMI connector was uses for speed, noise rejection, and signal purity. With-in the connection, there are balanced versions of the I2S interface that offer superior connectivity to any source which can output the signal. At the time this manual was written, the only component capable of outputting the balanced I2S signal is the PS Audio Perfect Wave Transport. In the very near future W4S will be coming out with a modification program which will offer proper circuitry to be added to many components for those who wish to benefit from this jitter-free connection. Please contact us for more information and current options.

So the DAC-2 would not currently allow me to go:

computer -> I2S -> dac

Also, the DAC-2's I2S input is via HDMI. I should have made clear that I am primarily interested in finding a dac that allows for I2S over ETHERNET. In other words, I would like to go:

computer -> I2S via ethernet -> dac

The only dac I know that is currently capable of this is the PS Audio PerfectWave dac, but, as I mentioned in the OP, it cannot be controlled with non-proprietary software like Amarra and Pure Music.

03-16-11: Aplhifi
Why I2S? You think it sounds best?

I don't know whether I2S has the potential to sound better than asynchronous USB, but I suspect that the answer is: maybe.

It seems like there are two basic consideration for the quality of the computer/dac interface.

1. The correct data.
2. The correct timing.

It is my understanding that I2S over ethernet (a) would allow for error correction; and (b) would be very low in jitter (jitter free?). If that is true, it would seem to be the most promising interface between the computer and dac.

In addition, it is my understanding that I2S is the native interface of most dac chips. If that is true, then there would seem to be an inherent advantage in sending an I2S signal from the computer to the dac, avoiding conversions to USB, S/PDIF, etc..

I understand that implementation is everything, so that the use of I2S does not guarantee good performance. It just strikes me as the most promising approach for SQ and future proof-ness (to the extent that exists).

I am happy to be wrong about any of this.

Bryon

Bryon,

I don't know whether I2S has the potential to sound better than asynchronous USB, but I suspect that the answer is: maybe.

1. Again, you always need an audio device somewhere on the line (Ethernet, USB, Firewire, PCI) to convert your audio files to I2S. There is no such thing as direct I2S from computer.

2. Why Ethernet? My understanding is that latency is much higher than USB and Firewire.

3. You can get I2S from any PCI audio card and some USB converters.

4. As already suggested, try the M2tech EVO I2S out connected to a DAC with I2S input.

5. There are 3 major audio data formats that DAC chips take. I2S is one of them, but not my favorite.

Best,
Alex Peychev

Bryon - I2S does not come direct from any computer. Nor is it related to Ethernet. Empirical Audio, as well as Northstar and Ayon use RJ-45 connector for I2S. Has nothing to do with Ethernet. Just using the connector.

Likewise, PSAudio uses HDMI connector for their "differential" I2S. Has nothing to do with HDMI spec. They are just using the connector.

I2S will generally deliver the lowest jitter to most D/A chips because this is their native interface, however an async reclocked USB interface driving I2S to a D/A chip in a DAC is about as good as you can get. This is assuming that the clock used for the USB interface is very low jitter, and the design and implementation is executed well.

Steve N.
Empirical Audio

Alex - I am interested in a dac that connects to the computer via ethernet so that (a) the data delivered to the dac can be error corrected; and (b) the computer can be placed at a significant distance from the dac (30 feet+).

Steve - Thank you for clearing up something that was confusing me -- I was under the impression that I2S and ethernet were somehow related. From your post, and from more reading, I see that they are not. So really what I'm looking for is a dac/computer interface that...

(1) ...is very low in jitter.

(2) ...allows the dac to communicate with the computer such that the data delivered to the dac is error corrected (as ethernet can, as I understand it).

(3) ...allows the computer to be placed far away from the dac (30 feet+).

(4) ...allows for the use of software, like Amarra or Pure music, that is not proprietary to the dac.

I don't know if such a thing exists, or could possibly exist, which is the reason for the OP.

Thanks for you help.

Bryon