How to know if MAN301DAC is using the original DAC or DAC-B (Golden DAC module)?
You can see from the right hand side of the MAN301.

Golden DAC module is a special fully balanced analogue output stage. It is based on Weiss own flagship OP1-BP amp module, which is a single-ended design. (This is why MEDEA+/MEDUS require 4pc x OP1-BP for stereo amplification). Golden DAC module also took the red LED light part from OP1-BP. When you see the red LEDs, that is the Golden DAC module.

Left photo: Golden DAC module: / Right photo: MEDUS OP1-BP modules