I myself have found the proper selection of power cords plus power conditioning products have a profound effect on audio quality. Living in an apartment makes it all the more important. And as I have previously stated, in the case of my OPPO 105 player, using a special, $400 JPS digital cord has a definite improvement in audio quality-even using a much costlier Audioquest power cord in it's place. On the other hand, the JPS power cord does not work as good as an Audioquest power cord if used with other audio components. By the way, when I got a used pair of Martin/Logan speakers, replacing the generic power cords with two Audioquest NRG power cords greatly improved loer frequency audio reproduction. And the two Audioquest Niagara 1000's that I am using also help bring audio reproduction to a higher level. The better the audio components used, the greater improvement will be realized with power cord-power conditioning used. Now even so, there are exceptions to at least the power cord question. I also have an 35 or soold Mcintosh MR74 tuner, which has it's own attached power cord. Plugged into my Audioquest Niagara 1000, itself connected to a wall socket witn an Audioquest NRG1000 power cord-the audio reproduction is amazing. With it's superior power supply, itcompletly outperformed my previous Day/Sequerrra FM Studio tuner-itselg using an $1280 Audioquest NRG100 power cord. But again, I have found that power cords generally have a profound effect on audio reproduction. As well as power conditioning.