Question on how DAC’s work...

"The Vault isn't unfolding MQA if you're passing the digital signal to another dac via digital out,"

This statement is not necessarily true. If the "external" DAC is MQA capable, you can select that as an option in BlueOS settings and allow the external DAC handle the unfolding.

The streamer (not the DAC) may partially unfold MQA, which is to 96/24, and send this decompressed signal down stream to a DAC.

Roon, for instance, does this. This is a great feature for me, since that allows me to do some subtle room correction in the digital domain.

You can often also turn streamer based unfolding off, and send the original, MQA encoded signal to the DAC where it will be unfolded if it can be.

In my experience, the sound quality difference between DAC's matters much more to me more than MQA support.

I have one of the early MQA devices and honestly, I didn't care for it. I'm with PS Audio and Benchmark on this whole thing, but to me, this also feels like a solution for a problem we had 20 years ago. Low bandwidth internet, and DACs which played MUCH better at high bit rates.

Now we have much faster internet, and much better DACs that can play Redbook as good as high rez music. So, meh.  I'd rather turn MQA off and pick the digital filter that sounds best.

Best,

E

My second question is if my disc player exports SACD at a different bit-rate than what the DAC is capable of, will the DAC upscale or alter the bit-rate to get better performance?

If you use digital out to an external dac the Denon will only do PCM you're not getting the SACD signal to the external dac so it will play the 16/44 layer. Of course some dacs can upsample/oversample. 

If your preference is to do Tidal MQA and you don't want to use the Bluesound Vault dac you would need a MQA capable dac to do the complete unfold. 

Thanks everyone...as usual, you've all been very helpful!

Arvin