Barking up the wrong tree, digital out from your MAC doesn't care about internal noise. Your MAC would be malfunctioning if 1's and 0's weren't being read correctly inside the case.
But your external D/A and analog equipment does care about how clean its power source is... ghost signals from other equipment power draws can reduce your tranparency during and after analog conversion.
But your external D/A and analog equipment does care about how clean its power source is... ghost signals from other equipment power draws can reduce your tranparency during and after analog conversion.