I would have to disagree with Rx8man.
I've upgraded the power cords on the power supplies of a Rega P9 and an SME 10 and heard the improvement the upgrade power cords made.
I don't think either power supply is underbuilt, but certainly isn't as demanding as an amplifier's power supply.
So I wouldn't be in too big a rush to prejudge any component. Feeling that it may not be worthy of a better power cord isn't the same as trying one and finding out for certain.
That said, if your system is resolving of differences in interconnect,speaker wire or component changes, then it should be capable of letting you hear what differences an upgraded power cord can make as well.
It's worth noting that the more power cords you change and if you keep them all the same,the better the end result is.
Expecting one power cord to change the sound of the whole system can be just too great an expectation.If one expects the sound of the High End,from entry level gear, a single upgraded power cord won't do it.An upgraded power cord as simple as it sounds, can really just change the component it's used in.
If several expensive power cords from the same manufacturer is keeping you out of the fun, then DIY.
Use the same connectors and wire on all your DIY cords.
I realize folks like to mix and match, and find wires that give more bass to some componets that seem to lack it.
But having been that route,consistency,clarity and coherence is more of what I strive for,so I tend to keep all my interconnects and power cords,the same thru out the system.
The power cords, as original equipment with the Quad 63 back when they were new in the 80's,were minimal,but judged to be all you would need by the manufacturer.
Which is/was a pity, because the sound of those speakers clearly improves when you improve the power cord.The same conclusion with stacked Quad 57, Martin Logan CLS and Acousta x speakers.
The better the power cord, the better the sound.
I would suggest hobbyists to address all electronic components the same,and not discriminate or assign any sort of hiarchy to one componet over the other.
Think of it as a system.Upgrade as a system.
Only then will the sound of the system truly be transformed and the importance of the power cords will be revealed in full.
I stated previously, my first foray into dIY /upgraded power cords.
Since that time,over 30 years,the stock power cord has always compromised the sound in any component I've ever owned.
No matter how sophisticated or simple it is.