@stereo5 a very common and incorrect impression based on the misinterpreted statement from a Pass Labs component manual. Putting this to bed.
Here’s that section verbatim…
Power Cords: Pass Labs provides a power supply cord that meets all legislated requirements for the market in which the product was originally sold. If you choose to substitute an aftermarket product we urge you to choose one that is fully safety rated by the necessary local authority.
In my experience, Pass Labs amps and preamps react to power cord changes exactly the same way as most other components do provided your system possesses the necessary resolving power, your room acoustics are up to the task and your ears are trained to hear these changes.