Can a power-supply upgrade produce audible sonic benefits? If you've upgraded the power supply of a phono preamplifier, you probably don't need to be convinced that it does, and those usually cost only a small percentage of the price of the model they power. But to add Simaudio's Moon Evolution 820S power supply ($8000) to the Moon Evolution 650D DACCD transport ($9000), which I reviewed in the November 2011 issue
, almost doubles
the latter's costthough the 820S can be used to simultaneously power two
Moon Evolution components, like the 750D DAC ($14,000), 740P preamplifier ($9500), and 610LP ($7500) and 810LP phono preamplifier ($13,000).