I'm not a measurement guy, though I find ARS reviews interesting. No more. Also, I'm aware that there's good evidence his measurements don't mean a lot. For example, he LOVES the Heresy but dumps on the Magni 3+, based entirely on measurements. But on aggregate most reviewers call it a coin toss or fall back on slight preferences. Currowong, for example, said he couldn't tell the difference and that one should pick according to which color one prefers; Zeos said it literally varied from headphone to headphone, etc. Josh Valour said he couldn't tell the difference. However, Armin is one of the very few who's bothered to review the Asgard with the 4490 card; most either review the A3 alone or the A3 with the MB.
I'm interested in the 4490 because it's cheaper, and because nothing I've read about the purported advantages of the MB convince me it's worth the extra money. I mean, yeah, maybe it's better, but only a little, and mainly it's about preference rather than performance. With all that said, Armin's argument is not that the sigma delta chip is bad, but rather that Schiit did a bad job of implementing it such that it hobbles the amp. Unfortunately, there are so few reviews about the A3 with 4490 that it's hard for me to tell if he's on to something or if this is just another example of his measurements leading astray. He has not reviewed an A3 with MB; I cannot tell if he would find that Schiit did a better job of implementing the MB or the same. However, there are lots of reviews of the A3 with MB, and they are overwhelmingly positive. That suggests that either Armin is right about the 4490 and that Schiit did a better job with the MB implementation, OR he's talking nonsense, and I can freely ignore him.
Are you following?
Of course, sound-wise the safer thing to do would be a modius or even a Modi, SD or MB, the Modius being the optimal choice. There's no disputing that. But then we're back to the issues that make the A3 w/ dac card appeal to me: budget + space + lack of wall warts. The space issue has me thinking maybe I should forgo the A3 in favor of a Modi/Magni stack; the issue then is the wall warts (the tangle of cables beside my desk is crazy, and the competition for space on my power strips intense). And of course, I'd always wonder what I'd be missing if I opted for a Magni rather than the A3...the difference is supposed to be fairly small, but meaningful.
At the moment I'm mainly pondering desk space. I cut a piece of paper to the dimensions of the Asgard and am pondering if it fits or if I should get a Modi/Magi stack. The Asgard with DAC offers some real practical advantages: no wall warts, less clutter. I've got a tangle of cables I really want to reduce, if possible, and certainly not make larger. A Modi/Magni stack is at least one wall wart.
Not going separates + trying to save space + money = making compromises. It's all a question of minimizing them. Armin's review suggests that maybe the A3/4490 represents a compromise that is larger than the one normally associated with choosing SD over MB. Maybe.