If possible, could you expand upon this comment. The Opera is much more expensive than the Aria. Are the improvements minor (like going from a cmoy to a Total BitHead) or pretty significant (like going from a $300 tube amp to a Raptor or SP SLAM). I am thinking about selling my Aria to fund one of these, and just want to know what I will be getting for my money.
What's hard to say is the delta in DACs, since I cannot audition them separately. The Opera is a signficant step up from the Aria as a Headphone amp, and Amp/dac combo, for sure. It has a combination of warmth and detail that is so rare in an audio componant.