Don't believe everthing you read from the reviewers! I own two sets of Martin Logans,Sequels and now Odyssey's and I myself have heard a change by using aftermarket power cords,It's not as big a change as on amps or preamps, or source units. I first tried Cardas Golden cross, and then the Whale Elite MK II's. I guess it depends on your power company,house,wiring,etc.