There's been a lot of talk about 432hz music on You Tube and other channels. This is my take on the subject, how it has changed how I approach music, as a listener and a creator.
Using a free cross platform digital audio workstation (Audacity) here I give you instructions on how to convert your 440hz music library to A432hz. Keep in mind that the original files should be tuned to A440 for accurate conversion. Additionally, it is expected that you own the music you're converting. Please, no piracy.
https://www.audacityteam.org