The concensus being that I shouldn't mess with my Schiit, I will
move on to other possible tweaks.
Just finding this thread. To add more detail, the Loki "wall-wart" is actually just a small transformer. If you look on the back of the Loki, the power socket says "16 VAC". This means 16 volts alternating current. The "wall-wart" transformer just reduces the 120V AC down to 16V AC. The rest of the linear power supply is inside the Loki. There have been other electronic devices that are designed this way, but it's very rare. The good thing here is that the transformer is far away from the Loki and will not produce electromagnetic interference inside the Loki.
So, yes, if you connect a 3rd party "DC" linear power supply, bad things could happen.
@jetter - this assumption is so easy to make because 99% of the time, these small units just use a real "wall-wart" switching power supply so a linear power supply upgrade would work just fine. However, when I look at possible upgrades to linear power supply I always try to examine the rear panel to see what the power requirement is. Usually it’s DC, such as 5V DC or 12VDC or something similar. In very rare cases, it is actually a, AC input (which can use the same barrel plug connector as other DC power supplies). If there's no print on the rear indicating power supply requirements, then I need to pull out my multi-meter to see what the power adapter is really producing.