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

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

But how come I2S is still not the digital standard for a CD transport and DAC interface

Mostly because it does not provide copy right protection, and other user programmable features.

As I mentioned, I2S is just one of the standards a DAC chip can take, such as MSB and LSB, but let's focus on I2S as you know it.

I2S contains 4 signal lines; data and 3 clocks. S/PDIF contains exactly the same unaltered signals, less the 4th line, the Master Clock. The real fault of S/PDIF comes from the PLL used to "recover" the Master Clock inside the S/PDIF receiver. This usually results in relatively very high jitter level and poor sound quality.

Providing a high-quality external Master Clock, or re-clocking solves all “issues” with S/PDIF. In my experience, such solution is not even a bit worse than I2S.

Best,
Alex Peychev

Bryon,

You're welcome!

Do you happen to know if the Mac mini can be controlled by an iPad?

Yes, I like iTeleport for remote desktop with PC and Mac.

Best,
Alex Peychev