Yes this AMR DP-777 has two dac chips inside, a "Classic" R2R Ladder Multibit and a "HD" Delta Sigma based one (for dsd replay), they can be switched on the fly while listening, everything else is the same. Here is what a reviewer said when he compared the sound of both of them when he played RedBook cd and PCM files through them.
"16/44 sources replay using the HD DAC"
If the sources are 16/44, the sound from the HD DAC is quite “HiFi”, seems to have more air and the treble energy is stronger. There is more siblings sound for the female vocal. But after a while, we can sense that it is missing some warmth in the mid range and the vocal is thinner than it should. The sound stage is quite shallow and the rise and fall of each music note is not as clear cut, the rhythm and pace is also less accurate, and finally the “musicality” of the DAC is reduced.
"16/44sources replay using the Classic DAC"
Now playing the 16/44 sources using the Classic DAC, the sound is a lot more natural, the 3D sound stage is back, there is plenty of space one can sense between the instruments, the vocal and instruments move back a few meters as there is now sound stage depth to take about, the rise and fall of each music note is much more clearly defined."
I remember reading somewhere Thorsten Losche (AMR’s designer) was asked why did you put in a Delta Sigma dac. As a token gesture for the HD crew, or similar was his answer.
Cheers George