# P5 phase change? **URL:** \ **Category:** Power Components\ **Created:** [June 23, 2017, 8:18am UTC](https://forum.psaudio.com/t/p5-phase-change/4067 "2017-06-23T08:18:06Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![robert891113](https://avatars.discourse-cdn.com/v4/letter/r/90db22/32.png) [@robert891113](https://forum.psaudio.com/u/robert891113)\ **Post date:** [June 23, 2017, 8:18am UTC](https://forum.psaudio.com/t/p5-phase-change/4067/1 "2017-06-23T08:18:06Z")
Hello, The thing that puzzles me most is the setting for “phase” on P5. I tried several tests: ``` Phase tune THD in THD out Multiwave (strength 6) Voltage out 0 1.4 0.1 no 120.1 0 1.4 1.6 yes 120.1 +10 1.4 0.1 yes 120.6 -10 1.4 2.5 no 119.3 ``` Are these numbers look normal? I will be thankful if someone can teach me what really is going on when I change the “phase tune”? Thanks ahead! ---
**Author:** ![Elk](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/elk/32/1240_2.png) [@Elk](https://forum.psaudio.com/u/Elk)\ **Post date:** [June 23, 2017, 9:14am UTC](https://forum.psaudio.com/t/p5-phase-change/4067/2 "2017-06-23T09:14:43Z")
Welcome, Robert It is rare phase tuning needs to be used. It is there to adjust the P5’s software to better phase lock loop synchronize with the incoming AC in certain odd circumstances. In these few cases it helps lower the THD. There is no harm playing with it. So try the various settings if you would like and listen for a difference. Use the setting that sounds bet. A little bit of technical info: The regenerator syncs with the zero crossings of the incoming voltage. However the peak of the incoming sine wave is usually not perfectly in the middle of the zero crossings, because of the phase of the distortion products. The regenerated wave thus has to be shifted slightly from the input. Typically, the difference is such the PowerPlant can do this on its own. However, the phase setting can be used when the phase difference is extreme. ---
**Author:** ![robert891113](https://avatars.discourse-cdn.com/v4/letter/r/90db22/32.png) [@robert891113](https://forum.psaudio.com/u/robert891113)\ **Post date:** [June 24, 2017, 1:19am UTC](https://forum.psaudio.com/t/p5-phase-change/4067/3 "2017-06-24T01:19:50Z")
Thanks for the info. I noticed that the output voltage can change with the phase change. Is that normal? ---
**Author:** ![Elk](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/elk/32/1240_2.png) [@Elk](https://forum.psaudio.com/u/Elk)\ **Post date:** [June 24, 2017, 7:18am UTC](https://forum.psaudio.com/t/p5-phase-change/4067/4 "2017-06-24T07:18:48Z")
I imagine so. Guessing, but it probably is a consequence of aligning/misaligning the peaks. I have not played with the phase adjustment in a very long time.