The best Neutral Power cord ?


I am looking to upgrade from the stock power cords on my amp, DAC and Preamp. First of all, do power cords really make a significant difference? If they do, what is the most neutral sounding power cord in the $100-300 range (used price of course. Do you have any suggestions? Please help.
kasboot
There is a DIY Bob Crump power cord for sale at the Audio Asylum Auction. Looks like the current bid is .05 so that should be in your budget :)
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Yeah Brulee I also LOL at *the performance sure sounded neutral tonight*. I have seen the word neutral used so often in trying to describe components that it can really lead to confusion in knowing where it lays. And yes I agree for whatever reason power cords do *sound* different. That is the ones that are good enough that I can discern a difference. I can't note too much difference at the lower end of the spectrum but as you move up it sure is evident. Lower noise floor and improved detail. I am of the opinion of Tom Nice, that more of the signal is coming through on the better cords and the RFI and nasties are filtered out by various means (dark matter?). End result, a quieter background leading to improved dynamics of the music and more inner detail is revealed, lifting another veil and getting closer to the recording. Are we at neutral yet?
I finally got to reading Stereophile,Dec. I see for a sidebar on PS Audio 600 they talk about power cords,and which one works best on their piece.They use the term neutral. Well I guess I was wrong about powercords being neutral;but you'll never get me to admit it.
Kasboot, I suggest you get started trying power cords. If you hear no significant difference, then your time spent auditioning them will be shorter, and you can get on with enjoying your system.