“If you want to understand the secrets of the universe, think in terms of energy, frequency and vibration”
Nikola Tesla

What do these words mean ?
A vibration is a movement up and down :

There are several aspects in music : the emotional and mental energy in it, the intention behind it, and the physics of it : its frequency, geometry, etc.
Positive intentions, emotions and thoughts in music can provide healing regardless of its physics, but proper physics can take the healing to a whole other level.

The 432hz tuning means that the middle A note will have that frequency. Then all the other notes will tune accordingly on different frequencies along the scale. So 432hz is just a reference point.
If you watch any orchestra or band, they will always tune together to the exact same reference point frequency. If even just one instrument is out of tune with the others, the whole thing will sound off.

Jamie Burtuff explains that European music before the early 50s, ancient Egyptian music, traditionally made Tibetan bowls and digeridoos, sitar Indian music, and many others, have been tuned to 432hz.

Around the second world war, the cabal studied which tuning would be the most harmful for humans, and as a result imposed the 440hz tuning via goebbels (who thought it was the best for war marches), and jc deagan. Musicians at the time protested against it but it was pushed through anyway. Almost all music has been tuned to that since then.

Since the new age movement, there has also been another tuning circulating called solfeggio, based on a middle C note of 528hz. This corresponds to a middle A of 444hz.
Although the numbers used for these frequencies do correspond to geometrical patterns found in nature, it appears they do not correspond to frequencies : as you can see in this video at the 6min6 mark , these frequencies are not harmonious between themselves, which means that it is not possible to play any music with them. So when you listen to music made with these frequencies, there can only be one note that will be part of this solfeggio frequency scale, and the rest of the music will not be part of it, which raises questions about its validity.

John Stuart Reid has shown the shape created by 432hz with cymatics (the science of making sound visible by vibrating water or other types of particles) :

SNIP