I did a little experimenting using as a dac today. Michael has already stated because of how clean the output is that it can be used as a dac with the volume at 3:00 if I remember correctly. The results have been interesting. First I tried it with all switches to the left(default) and volume at 3:00. I was pretty disappointed with the results. The sound was clean, but it was significantly lower than the source I was comparing it to(marantz sa8004). The bass was anemic, sound stage collapsed, the treble sounded shrill, and the mids were thin. The overall all sound was a bit cold sounding.
I immediately thought something was wrong and double checked the settings and they were all correct. Then I tried turning the volume all the way up(it goes to 5:00). The sound really didn't get louder(maybe just a hair), but it became a bit muddy. So I guess it's safe to assume I remembered correctly when Michael said turn the pot to 3:00 to use as a dac. So at this point I'm thinking this unit is pretty much fail using it as a dac. So given how low the output was, I thought I would try it with the gain bumped to the second position.
Well "Houston we have lift off"!! Everything changed. Going back to my marantz, the sound level sounds identical. This is very surprising. I'm now wondering if the default gain was toned down to compensate for using iems because it's significantly lower than the line out from my other sources. The bass has now returned, and gone is the thin sounding mids, and shrill highs. This is very surprising, but nonetheless, I can now move on to doing some serious listening using it as a dac.
First of all, with the volume at 3:00 and the gain in the second position, the sound is really clean with a fairly black background. Compared to my sa8004, it's a bit closer than I was expecting. There's just a hint of grain in the mids, and the bass doesn't dig quiet as deep with just a wee bit less slam compared to the marantz. But overall it's still closer than I was expecting. They both do have some similarities though. They both are slightly on the warmer side of neutral(a good thing for me), so they tilt more toward th analog and musical side of things than the analytical side. The center image of the marantz puts you a couple of more rows back, but the sounds stage width is really close between the two.
But on the other hand, of course I can't use the same interconnects with the two given the 1/8 inch and 1/4 inch single ended. And also, I'm using 6n silver interconnects on from my marantz. And this was using cd playback on the marantz vs ipad/m8 combo(using my iphone 5 as a remote with the ipeng app). I do plan to use it as a spdif converter as soon as I find my optical to 1/8in adapter. Using it as a dac only, I would easily put it on par with a music streamer pro I recently sold and a little above a musical fidelity vdac II I use to have. I'm going to compare it to my stagedac later. Now that should really be an interesting comparison.