From MH Wiki
the ULN-8 and LIO-8 both set the AES bit flag to Consumer on output. This can cause trouble with limited devices that only accept the professional bit flag for input. the ULN8/LIO accepts any valid AES input regardless of of flag status.
Disable Front Panel Power
jumper position J7 on the PSU board (by the power switch connector) bypasses the front panel power switch.
the ULN-8 has +90 dB of gain on recallable headamps
At 12 Volts the current demand for a single ULN-8 is: 3-3.5A
the minimum power requirement for the 2.1mm on the ULN-8 is 16V
the minimum power requirement for the 4pin XLR plug on ULN-8 is 12V