Or ASIO native.

according to the manual  I just read that
It can convert dsd to pcm.
It can use Dop dsd over pcm.  And it can definitely decode dsd Native.
Chapter 17.1

I think I have answered my own question

> It can convert dsd to pcm.

DAC chips in DACs play DSD stream by converting it to PCM first. Otherwise volume control won't work. Any other DAC products (based on AKM or ESS chips) that has digital volume control do exactly the same.

"Direct DSD" in your first question means bypassing PCM conversion for the DAC chip. In this case, you lose volume control.

If you are asking whehter it can convert DSD from digital inputs (such as USB) to PCM streams, and sending it to digital outputs (such as SPDIF, COAX, etc). No, it cannot do that.

> It can use Dop dsd over pcm.

Right. All digital inputs accepts DOP.

> And it can definitely decode dsd Native.

Depends on how you interpret it.

If you solely refer "DSD Native" as UAC Alternative Setting 3 such as many other USB audio interface chips (such as XMOS) support, it's NOT supporting that. It does not behave the same as many other DACs (such as XMOS based products) do.

It does support "ASIO native DSD", but in my understanding (edit: MC just confirmed my hypothesis), it's just using the RME ASIO driver to convert native DSD to DOP on your computer first, and then send the DOP signal to the unit via USB. The conversion is seamless so you don't need to care about it in Windows. For any other operating systems you can't set your music player to output "native DSD" to the unit.

So the conclusion is, NO, the unit itself cannot decode "DSD native" from the digital inputs. Only DoP. The Native -> DOP conversion is done on your computer.

> the unit itself cannot decode "DSD native" from the digital inputs

'Digital inputs' would refer to AES/SPDIF, not USB. I have never seen something different than DoP used there. Which is no wonder as you only have 24 bits available to transfer data. UAC AS3 uses 32 bits.