Worth to mention is that there are many alternative frequencies for tuning. Some people say 444 Hz is the "sacred frequency" but so far there is no "right" or "wrong" tuning defined. There are claims that 432 Hz was the standard tuning for classical composers, but this is not true. There was no such thing as a standard tuning before electromagnetism was discovered in the 19th century, which enabled the precise measurement of frequencies. Old organ pipes are tuned to a large variety of frequencies.
"For example, an English pitchpipe from 1720 plays the A above middle C at 380 Hz, while the organs played by Johann Sebastian Bach in Hamburg, Leipzig and Weimar were pitched at A = 480 Hz, a difference of around four semitones. In other words, the A produced by the 1720 pitchpipe would have been at the same frequency as the F on one of Bach's organs."
With this being said, my own personal experience with the different frequencies has been clear. I feel a lot more relaxed when playing 432 Hz on my guitar, maybe partly because there is less tension on the strings. However, there is also a connection to sacred numbers. An lower octave is half the frequency and a higher octave is double frequency. The A string (second lowest) on a guitar that is the one being tuned is two octaves below the tuning A, which means four times lower frequency. For 440 Hz this becomes 110 Hz, but for 432 Hz it becomes 108 Hz, which is a sacred number. (See Wikipedia)
However, this discussion doesn't take something crucial into consideration: just intonation compared to equal temperament. I will attend to this topic in my next article.