Prioritizing Power Cable Upgrades by System Component.

If you have not done any upgrades yet, start with W Audio power cables that you can get for about $50 each on Amazon and then pick up a true audiophile cable brand and try it in different places in your system.  A W Audio power cable made a significant improvement on my integrated.  I can't say that it did anything for either my DAC or power conditioner, but I have not spent a lot of time trying to isolate it one way or the other.  I've a lower level audiophile that isn't after improvements that I have to repeatedly A/B to identify a different or preference.  The W Audio power cord was a clear improvement for my Pathos Classic One MKIII that I recognized immediately.  It was significant enough that it started me down the path of exploring cables a bit when I had mostly been a cable agnostic before.

I have upgraded power cables a couple times. About 25 years ago and over the last couple years. Having just made the final decision on the most important component in my system, the amp… I am done for a while. See my User ID for my systems.

So, make sure you got your speaker cables and interconnects dialed in. I think I would then go for the amp… that was by far the biggest difference in no small way for me. You want a high current design. 

it depends on your equipment but think on the order of 10% the value of your component. My amp, for instance cost $22K, and I tested power cords from $800 to $3500… I found that a $1,800 was jaw dropping lay good. You cannot choose exclusively by price. But if you have a $5K component look at the $500 range… and even better look in that range used from UsedCables. 
 

Power cables typically are the last, but really important change that can make a big difference.

on another thread one member here made a good point

the influence of the power cable is inversely proportional to the quality and sophistication of the built in power filtering and power supply of any component... i think there is wisdom in this... and i would say, over time, units like pass labs --  which has exceptional power supply and filtering design -- reacts minimally to aftermarket power cables