I think it would be interesting to re-read Emile's explanations about his new DAC-Server interface.
“For some time, the question on many people’s collective minds was: “When will Taiko bring some form of DAC to market?”
As you all know we have been advocating the use of the USB interface to connect to your DAC while most other server vendors advocate the use of SPDIF/AES/I2S and in a few rare cases Ethernet. The reasons for this are pretty straightforward.
You aspire to meet or exceed cd transport playback performance for 16/44.1 files at a competitive retail price level. This first issue you will run into is a quite obvious one, you need a very significantly larger amount of PCB real estate, functionality and processing power which require much more filtering to have competitive electronics noise levels. You could argue that a CD transport comes with additional expense for rotational stability and vibration control (jitter) but then you're disregarding the streamer hardware possibly being equally sensitive to this, but you do have the luxury of the
absence of a motor. Then you need an interface to the DAC. Very low noise SPDIF/AES/I2S solutions have been around for decades with not much, if any, mystery surrounding their sound quality performance. And obviously, using the same interface as a CD transport, it becomes easier to approach a CD transport sound signature. However, with a limitation of a 24/192 data rate over a single line, and due to how the interface works, increased noise levels at higher sample rates. Typically, this interface will not sound better for higher sample rate files than 16/44.1 (note that the source master quality tends to exceed any of these differences at all time), and worse than 16/44.1 with DSD/DXD files due to the need of significant conversion processing. Ideally you have managed to have CD transport quality playback, for all sampling rates... To us this has been an unacceptable approach from day 1, which is why we went all in on USB. USB data packet rate is fixed and does not change with sampling rate, the interface is universal, the interface sound signature does not change with sampling rate, and it's the same for all receivers, or at least, that was the design goal... Today we know and have proven this is not true. Sure, we have developed an USB card with noise levels at or below those of an AES/SPDIF/I2S interface without the jitter/timing sensitivities of those interfaces. But still there were deviations and discrepancies from expected performance. It took designing our own USB driver, querying all DACs our customers support, and designing our driver to be adjustable to... different implementations of USB receivers in DACs. This was quite an elaborate project, but as you have all witnessed the performance delta can be dramatic. However, as you also all know by now is that the playback software has its signature too, and Roon's signature has changed over time. Roon currently sounds more expansive than the average CD transport, but also softer and less clear, and some prefer this over CD, some don't. We now have XDMS (currently in Alpha state) to level the playing field once more. For 16/44.1 (local file playback), XDMS on the Extreme sounds like a mix of CEC TL0 3.0 timing, Kalista color shading, and the bass of a Mark Levinson 31.5. We like to think that what we have today is competitive performance at 16/44.1 to top flight CD transports, and we deliver on the promise of better performance at higher sample rates (again assuming corresponding master quality).”