When I was about 18 I got a guitar tuner for x-mas. Being a fan of Jimmy Page I was interested in alternative tunings. I don't recall any mention of tuning down from the standard 440HZ-432HZ though. I do recall using the tuner and always tuning to the left of the needle a ways. Who knows perhaps I was just trying to get the strings to bounce more or have less tension since I preferred to use my fingernails to play guitar. One thing is for certain my tuner did not have 432HZ marked but where I was gravitating I was right around that frequency.
I've heard the 440HZ was started by the nazis because their equipment was tuned to that. Before dismissing that just look at how many things we copied from them. our rocket technology grew out of the kidnapping of their scientists. Our troops wear nazi helmets. Some of our presidents such as junior bush has close family ties with hitler. Since the world has been fucked up in a very bad way since wwII I think it's safe to say 440HZ was chosen for the wrong reasons.
There were several movements to make everything 440HZ the years prior to the Nazis. I guess the French were left out of one consideration which made them very irate. The French do get emotional.
432HZ is the frequency Stradivarius used to tune those fiddles he made.
Some people can break down frequencies to the molecule. I am not one of those people. What I can do is tell you 432HZ seems to have very nice harmonics. Some people would not like these overtones. Another thing is I found myself finding the notes as if something was guiding me. The significance of this is I was playing bass guitar and I am not overly familiar with bass. The notes seem to come out of no where. I'm not saying I was playing like James Jamerson but I was playing better than I did a few minutes before in 440HZ and in slightly off 432HZ.
What I did in Guitar Rig was set the tuner to chromatic, change reference pitch to A4-432HZ, and tune the 1st A on the fret board of each string. Works for me. Sounded great. I just need to build up the strength in my fingers to play bass.
Some side effects can be experienced such as wanting to get completely naked and storm a high brow tea party and announce to a comatose crowd you've found your true calling in life but these are perfectly normal. Some other things you might experience is you'll need your action adjusted a bit or you might have to play more gently.