my system

[Jean-Marie]

That assumes that there is no way to best the Roon replay and internal D1000 DAC combination, which isn’t obvious.

I am of course aware that the analog signal coming out of the Esoteric will be converted to digital again in the D1000 but still.

And then there is of course the subjective preference of sound converted one way or another.

Anyway, so far your forecast matches my perception. :-)

Cheers,
Bernard

Bernard,

Yes I am making two assumptions: 
1) Since all 4 options are using the internal DAC of the D1000 (you cannot do otherwise with the Devialet anyway), the simpler way to bring in bit perfect source to this DAC is the better
2) Roon/RAAT is bit perfect

Cheers,
Jean-Marie

Those are reasonable assumptions, 

Out of curiosity, do you think that all DAC sound the same? Also, what are the KPIs you consider relevant to assess the ability of a DAC to do its job?

Cheers,
Bernard

From my perspective, the chain is the following: Low Pass Filter (Anti Aliasing)-> ADC -> DAC -> Low Pass Filter (Reconstruction).

If you are semi-competent in your design and implementation the ADC -> DAC stage is nowadays transparent and the noise floor and distortion is pretty much well below the hearing threshold.

So what remain are the filters and I think they are the most important characteristics of the DACs and the highest contributors to their difference in sounding

The Devialets are a bit of a special situation because DAC is intimately bounded to the amplifier and in fact parts of the amplifier work in the digital domain. Also, I may be wrong, but I believe the amplifier is part of the reconstruction filter, contributing to it's exceptional transparency (at least in my opinion as well as measurements)

Please note that the transparency of the ADC/DAC operation explains why a Devialet accurately propagates the personalities of external DACs that you can put in front of it, even if it will go into the internal ADC and DAC of the Devialet.

So to answer your initial question, the most important characteristic of a DAC is its analog part (the reconstruction filter and the circuitry that will drive its analog outputs). And I'm convinced that any difference of sound between DACs is primarily coming from this part.

Jean-Marie