As might be expected, opinions on this question will differ. See this thread, which addressed a similar question. My opinion was summarized in the first of my posts in that thread dated 1-5-12, in which I said:
-- Al
01-05-12: AlmargRegards,
I see no reasonable plausibility in the expectation that given power cord characteristics will result in effects on the sound that are consistent across components that perform different functions, that have vastly different fluctuations in their power draw, that have vastly different amounts of power draw, that generate different amounts of rfi, that can be presumed to have different rfi sensitivity, that interpose completely different power supply designs between the AC and the signal path, and that may be completely different designs in just about every other respect.
-- Al