Ah, one thing that the Merason POW1 linear power supply has that all other generic external linear power supplies do not are 3 different power supplies internally. The POW1 connection cable is actually a special 5-pin DIN cable. It has power supplies for digital section (probably 5V), and two separate rails for I/V analog section (this is something like a +15V line and a -15V line, but it could be any voltage). The important part is the analog section works better with a + and a - voltage power supply line.
Most DACs that have internal linear power supplies (like the LKS 005) do have multiple power supplies. My LKS 004 dac actually has 6 separate power supplies internally (2 for analog I/V, 3 for digital, 1 for controller and front panel). The LKS 005 most likely has 6 power supplies as well (it follows Musetec approach).