I knew my DAC is good, but I wasn't aware of such comparison made.
I'm feeling a bit happier now. Curious as to how much improvement I would get from the Phoenix too. Too bad the UD100 has no volume control, I had to get the E11 later for that. Worth every cent however. A new question would be, am I willing to spend money to get that Phoenix for comparison? lol.
A DAC is just a digital to analog converter. It's not supposed to have a volume control. That's what a headphone amp is for, to take the signal from the DAC and reduce and/or amplify it louder with more power. The Phoenix is just a DAC and headphone amp rolled into one.
Since the UD100 is apparently a pretty good DAC, then it's probably the SQ of the headphone amp for the Phoenix vs the E11 that would be the major difference, if any.