I also used a good quality Tripp-Lite surge protector/noise filter and Transparent PowerLink Plus from the Tripp-Lite to the Creek 5350SE Integrated amp. Compared to a stock power cord, the Transparent with the filter networks took out some of the hardness in the sound, brought out more of the harmonics and increased the transparency - worth every $120 of the price.
I bought a Monster Cable HTS-2500 2 months ago to replace the Tripp-Lite and that made a even more worthwile improvement. Now the harmonic structure is even better, the transparency is greatly increased, the images are better focused, the upper and midbass are fuller with more impact and the sound is more naturally sweet. The improvement in musicality is easily perceived.
The Monster Power Center HTS-2500 brought a more worthwhile performance improvement than the powercord. You can find a good used HTS-2500 on Audiogon for about $150.00. Hope my experience helps you.