I'm considering the A6 vs the Master Edition for use as streamer only to an external DAC via USB. In that configuration, does the ME provide any advantages over the base A6? My understanding is that USB out uses the clock in the DAC, not the streamer, so the upgraded femto clocks in the ME don't provide an advantage. Is that accurate?
Save your money and get the regular one
The DAC in the regular A6 is great. Why would you have it output to an external DAC that can't and won't improve anything?
I mostly agree with this claim, but it depends on where/what exactly are you looking at. Let me explain.
If I take two delta sigma DACs and compare side to side (not A/B) I just can’t find a difference. I have tried many DACs from $70 to $700 USD (SMSL SU-1 to Topping D70PRO and a few other in between including DMP-A6) and they’re all the same to me. 95% of my listening is on speakers + sub so I am taking headphones out of the equation.
But I decided to try something different and this is where I finally noticed a difference. I went ahead and purchased an R2R DAC (Musician Pegasus II) and to my surprise I finally noticed something palpably different. Granted, I can only find differences in the low end, that’s it. Delta Sigma DACs have more punchy and controlled bass. R2R bass is smoother (perhaps a bit too much for my taste) but I do like this "softness" sensation on my speakers.
My system allows me to output to two different DACs at the same time, like this:
So without going into too much detail, I found out I prefer to use delta sigma DACs (as cheap as possible) to handle the low end (low pass from 70Hz down to my sub) and my Pegasus II to handle mids to highs (high pass from 70Hz and up to my speakers). I have come to the conclusion that this combination provides the best results for my setup and now I don’t worry about upgrading anymore.
But again, as far as I can tell, the only differences are detectable to me in the low end. Nothing else. Why? I don’t know. Is it measureable? I don't know and maybe I don’t even care but it works for me.