Voltage on PS Power plant make a difference?

I have a PS Audio P500 and it works ok. I recently upgraded all my ac cable to expensive but good cords. My cords are all prototype cords from the same manufacturer but never made it to production. They are not the cords you may see advertized on audiogon as the next new best power cord available. They are actually of high quality and the proof is in the listening. My last cord I changed was to a King Cobra V2 to my CDP and after a while I noticed the sound was too slow and lacked punch and "snap". While investigating the P500 on the PS Audio forum I noticed that somebody tried changing the voltage settings with positive results. As I figured I had nothing to lose I decided to up the voltage of my power plant from the 117V which is factory preset to 120V with dramatic results. I now have the punch and snap back in my system as well as the smooth sound of the King CobraV2. I was just wondering if anybody else notices a difference between varying voltage settings with power plants or other Conditioners with adjustable voltage settings. Does it make sense to have this dramatic change of sound with a 3 volt increase in voltage or is it that something else may be happening in my system? Any opinions would be appreciated.
I also got sonic improvement by turning up the voltage from 117V to 120V.
I guess it is equipment dependent. In my case there was no difference that I could detect.
I'm either loosing my mind again or there is a DRASTIC difference(in my system)by upping the voltage to 120V from 117V. Before I changed the voltage setting my sound had an artificial sound to it which I attributed to the P500. After living with the upped voltage on a setting I find tends towards slightly bright with the P500 I decided to keep the voltage at 120V and change the P500 Multiwave setting to the most natural setting the power plant has to offer in my system and now I'm so excited that I had to write this comment on this post. I am using a Shunyata King CobraV2 to CDP which from day one seemed to slow the sound down very much but with the recent changes in voltage I'm happy that my system sounds the way that it does. Full but tight bass(I did not know one could get both these attributes at the same time),mids that are smooth without grain I can detect and the highs are delicate but very detailed. My system has never ever sounded so natural and yet with tons of dynamics.I know I have a whole lot to learn and peoples comments and advice would be greatly appreciated.