I wasn't aware the dac in the DAC-100 runs in class A... I don't see anything about it in the literature. But even then, the psu on the right side is hotter in the DAC. Maybe that's because it has to power more components in the DAC-100 compared to the HAP-100? Just curious about it, that's all.
Later this week I plan to borrow a Schiit Bifrost and Lyr (and if my friend is feeling generous maybe his LCD2) to do some comparison.
I have the Nuforce power supply with the 192k usb converter as well, which can feed the DAC-100 and Bifrost simultaneously, and feed those both into the HAP-100 (and possibly into the Icon2 into HE-6 later on). for a good head to head of the dacs. I might throw the iBasso D10 and some others into the mix if I'm not worn out of listening by then. Heck I could do a FiiO e10 coax out into one of the dacs as well...